path: root/Build/source/texk/web2c/doc/web2c.info

This is web2c.info, produced by makeinfo version 6.7 from web2c.texi.

This file documents the installation and use of the programs in Web2c,
an implementation of Donald Knuth's TeX system.

   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
2005, 2007, 2008, 2009, 2010-2020 Karl Berry & Olaf Weber.

   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided that the
entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a
translation
INFO-DIR-SECTION TeX
START-INFO-DIR-ENTRY
* Web2c: (web2c).               TeX, Metafont, and companion programs.
END-INFO-DIR-ENTRY

INFO-DIR-SECTION Individual utilities
START-INFO-DIR-ENTRY
* bibtex: (web2c)bibtex invocation.             Maintaining bibliographies.
* dvicopy: (web2c)dvicopy invocation.           Virtual font expansion
* dvitomp: (web2c)dvitomp invocation.           DVI to MPX (MetaPost pictures).
* dvitype: (web2c)dvitype invocation.           DVI to human-readable text.
* gftodvi: (web2c)gftodvi invocation.           Generic font proofsheets.
* gftopk: (web2c)gftopk invocation.             Generic to packed fonts.
* gftype: (web2c)gftype invocation.             GF to human-readable text.
* mf: (web2c)mf invocation.                     Creating typeface families.
* mft: (web2c)mft invocation.                   Prettyprinting Metafont source.
* mltex: (web2c)MLTeX.                          Multi-lingual TeX.
* mpost: (web2c)mpost invocation.               Generating PostScript.
* patgen: (web2c)patgen invocation.             Creating hyphenation patterns.
* pktogf: (web2c)pktogf invocation.             Packed to generic fonts.
* pktype: (web2c)pktype invocation.             PK to human-readable text.
* pltotf: (web2c)pltotf invocation.             Property list to TFM.
* pooltype: (web2c)pooltype invocation.         Display WEB pool files.
* tangle: (web2c)tangle invocation.             WEB to Pascal.
* tex: (web2c)tex invocation.                   Typesetting.
* tftopl: (web2c)tftopl invocation.             TFM -> property list.
* vftovp: (web2c)vftovp invocation.             Virtual font -> virtual pl.
* vptovf: (web2c)vptovf invocation.             Virtual pl -> virtual font.
* weave: (web2c)weave invocation.               WEB to TeX.
END-INFO-DIR-ENTRY


File: web2c.info,  Node: Top,  Next: Introduction,  Up: (dir)

Web2c
*****

This document describes how to install and use the programs in the Web2c
implementation of the TeX system, especially for Unix systems.  It
corresponds to Web2c version 2020, released in June 2020.

* Menu:

* Introduction::                A brief introduction.
* Installation::                How to compile and install Web2c.
* Commonalities::               Option syntax, standard options, memory dumps.
* Three programs::              TeX, Metafont, MetaPost have much in common.
* TeX::                         Typesetting.
* Metafont::                    Typeface design.
* MetaPost::                    Technical illustrations.
* BibTeX::                      Reusable bibliographies.
* WEB::                         Literate programming.
* DVI utilities::               DVI expansion.
* Font utilities::              Font format conversion.
* Legalisms::                   Blah blah blah.
* References::                  Books and such.
* Index::                       General index.


File: web2c.info,  Node: Introduction,  Next: Installation,  Prev: Top,  Up: Top

1 Introduction
**************

This manual corresponds to version 2020 of Web2c, released in June 2020.

   "Web2c" is the name of a TeX implementation, originally for Unix, but
now also running under various operating systems.  By "TeX
implementation", we mean all of the standard programs developed by the
Stanford TeX project directed by Donald E. Knuth: Metafont, DVItype,
GFtoDVI, BibTeX, Tangle, etc., as well as TeX itself.  Other programs
are also included: DVIcopy, written by Peter Breitenlohner, MetaPost and
its utilities (derived from Metafont), by John Hobby, etc.

   General strategy: Web2c works, as its name implies, by translating
the WEB source in which TeX is written into C source code.  Its output
is not self-contained, however; it makes extensive use of many macros
and functions in a library (the 'web2c/lib' directory in the sources).
Therefore, it will not work without change on an arbitrary WEB program.

   Availability: All of Web2c is freely available--"free" both in the
sense of no cost (free ice cream) and of having the source code to
modify and/or redistribute (free speech).  *Note
(kpathsea)unixtex.ftp::, for the practical details of how to obtain
Web2c.

   Different parts of the Web2c distribution have different licensing
terms, however, reflecting the different circumstances of their
creation; consult each source file for exact details.  The main
practical implication for redistributors of Web2c is that most of the
executables are covered by the GNU General Public License or GNU Lesser
General Public License, and therefore anyone who gets a binary
distribution must also get the sources, as explained by the terms of the
GPL (<https://gnu.org/licenses/>.  The GPL covers the Web2c executables,
including 'tex', because the Free Software Foundation sponsored the
initial development of the Kpathsea library that Web2c uses.  The basic
source files from Stanford, however, have their own copyright terms or
are in the public domain, and are not covered by the GPL.

   History: Tomas Rokicki originated the TeX-to-C system in 1987,
working from the first change files for TeX under Unix, which were done
primarily by Howard Trickey and Pavel Curtis.  Tim Morgan then took over
development and maintenance for a number of years; the name changed to
Web-to-C somewhere in there.  In 1990, Karl Berry became the maintainer.
He made many changes to the original sources, and started using the
shorter name Web2c.  In 1997, Olaf Weber took over, and then in 2006,
Karl started taking care of it again.  No significant development or
changes have been needed for many years.  Dozens of other people have
contributed; their names are listed in the 'ChangeLog' files.

   Other acknowledgements by Karl: The University of Massachusetts at
Boston (particularly Rick Martin and Bob Morris) provided computers and
ftp access to me for many years.  Richard Stallman at the Free Software
Foundation employed me while I wrote the original path searching library
(for the GNU font utilities).  (rms also gave us Emacs, GDB, and GCC,
without which I cannot imagine developing Web2c.)  And, of course, TeX
would not exist in the first place without Donald E. Knuth.

   Further reading: *Note References::.


File: web2c.info,  Node: Installation,  Next: Commonalities,  Prev: Introduction,  Up: Top

2 Installation
**************

(A copy of this chapter is in the distribution file 'web2c/INSTALL'.)

   Installing Web2c is mostly the same as installing any other
Kpathsea-using program.  Therefore, for the basic steps involved, see
*note (kpathsea)Installation::.  (A copy is in the file
'kpathsea/INSTALL'.)

   One peculiarity to Web2c is that the source distribution comes in two
files: 'web.tar.gz' and 'web2c.tar.gz'.  You must retrieve and unpack
them both.  (We have two because the former archive contains the very
large and seldom-changing original WEB source files.)  *Note
(kpathsea)unixtex.ftp::.

   Another peculiarity is the MetaPost program.  Although it has been
installed previously as 'mp', as of Web2c 7.0 the installed name is now
'mpost', to avoid conflict with the 'mp' program that does
prettyprinting.  This approach was recommended by the MetaPost author,
John Hobby.  If you as the TeX administrator wish to make it available
under its shorter name as well, you will have to set up a link or some
such yourself.  And of course individual users can do the same.

   For solutions to common installation problems and information on how
to report a bug, see the file 'kpathsea/BUGS' (*note (kpathsea)Bugs::).
See also the Web2c home page, <http://www.tug.org/web2c>.

   Points worth repeating:

   * Before starting the standard compilation and installation you must
     install the basic fonts, macros, and other library files.  *Note
     (kpathsea)Installation::.

   * If you do not wish to use the standard file locations, see *note
     (kpathsea)Changing search paths::.

   * Some Web2c features are enabled or disabled at 'configure' time, as
     described in the first section below.

* Menu:

* configure options::           Especially -with and -enable.
* Compile-time options::        Unusual -D's.
* Additional targets::		Breaking down the task.
* Triptrap::                    Running the torture tests.


File: web2c.info,  Node: configure options,  Next: Compile-time options,  Up: Installation

2.1 'configure' options
=======================

This section gives pointers to descriptions of the '--with' and
'--enable' 'configure' arguments that Web2c accepts.  Some are specific
to Web2c, others are generic to all Kpathsea-using programs.

   For a list of all the options 'configure' accepts, run 'configure
--help'.  The generic options are listed first, and the package-specific
options come last.

   For a description of the generic options (which mainly allow you to
specify installation directories) and basic 'configure' usage, see *note
Running 'configure' scripts: (autoconf)Invoking configure, a copy is in
the file 'kpathsea/CONFIGURE'.

'--disable-dump-share'
     Do not make fmt/base/mem files sharable across different endian
     architectures.  *Note Hardware and memory dumps::.

'--without-maketexmf-default'
'--without-maketexpk-default'
'--without-maketextfm-default'
'--with-maketextex-default'
     Enable or disable the dynamic generation programs.  *Note
     (kpathsea)mktex configuration::.  The defaults are the inverse of
     the options, i.e., everything is enabled except 'mktextex'.

'--enable-shared'
     Build Kpathsea as a shared library.  *Note (kpathsea)Shared
     library::.

'--with-editor=CMD'
     Change the default editor invoked by the 'e' interactive command.
     *Note Editor invocation::.

'--with-epsfwin'
'--with-hp2627win'
'--with-mftalkwin'
'--with-nextwin'
'--with-regiswin'
'--with-suntoolswin'
'--with-tektronixwin'
'--with-unitermwin'
'--with-x'
'--with-x-toolkit=KIT'
'--with-x11win'
'--with-x11'
     Define Metafont graphics support; by default, no graphics support
     is enabled.  *Note Online Metafont graphics::.

'--x-includes=DIR'
'--x-libraries=DIR'
     Define the locations of the X11 include files and libraries; by
     default, 'configure' does its best to guess).  *Note
     (autoconf)Optional Features::.  A copy is in 'kpathsea/CONFIGURE'.


File: web2c.info,  Node: Compile-time options,  Next: Additional targets,  Prev: configure options,  Up: Installation

2.2 Compile-time options
========================

In addition to the 'configure' options listed in the previous section,
there are a few things that can be affected at compile-time with C
definitions, rather than with 'configure'.  Using any of these is
unusual.

   To specify extra compiler flags ('-DNAME' in this case), the simplest
thing to do is:
     make XCFLAGS="CCOPTIONS"
You can also set the 'CFLAGS' environment variable before running
'configure'.  *Note (kpathsea)configure environment::.

   Anyway, here are the possibilities:

'-DFIXPT'
'-DNO_MF_ASM'
     Use the original WEB fixed-point routines for Metafont and MetaPost
     arithmetic calculations regarding fractions.  By default,
     assembly-language routines are used on x86 hardware with GNU C
     (unless 'NO_MF_ASM' is defined), and floating-point routines are
     used otherwise.

'-DIPC_DEBUG'
     Report on various interprocess communication activities.  *Note IPC
     and TeX: IPC and TeX.


File: web2c.info,  Node: Additional targets,  Next: Triptrap,  Prev: Compile-time options,  Up: Installation

2.3 Additional targets
======================

Web2c has several Make targets besides the standard ones.  You can
invoke these either in the top level directory of the source
distribution (the one containing 'kpathsea/' and 'web2c/'), or in the
'web2c/' directory.

'c-sources'
     Make only the C files, translated from the Web sources, presumably
     because you want to take them to a non-Unix machine.

'formats'
'install-formats'
     Make or install all the memory dumps (*note Memory dumps::).  By
     default, the standard plain formats plus 'latex.fmt' are made.  You
     can add other formats by redefining the 'fmts', 'bases', and 'mems'
     variables.  See the top of 'web2c/Makefile' for the possibilities.

'fmts'
'install-fmts'
     Make or install the TeX '.fmt' files.  *Note Initial TeX::.

'bases'
'install-bases'

     Make or install the Metafont '.base' files.  *Note Initial
     Metafont::.

'mems'
'install-mems'
     Make or install the MetaPost '.mem' files.  *Note Initial
     MetaPost::.

'triptrap'
'trip'
'trap'
'mptrap'
     To run the torture tests for TeX, Metafont, and MetaPost
     (respectively).  See the next section.


File: web2c.info,  Node: Triptrap,  Prev: Additional targets,  Up: Installation

2.4 Trip, trap, and mptrap: Torture tests
=========================================

To validate your TeX, Metafont, and MetaPost executables, run 'make
triptrap'.  This runs the trip, trap, and mptrap "torture tests".  See
the files 'triptrap/tripman.tex', 'triptrap/trapman.tex', and
'triptrap/mptrap.readme' for detailed information and background on the
tests.

   The differences between your executables' behavior and the standard
values will show up on your terminal.  The usual differences (these are
all acceptable) are:

   * string usage and table sizes;
   * glue set ratios;
   * 'down4', 'right4', and 'y4' commands in DVItype output;
   * dates and times.

Any other differences are trouble.  The most common culprit in the past
has been compiler bugs, especially when optimizing.  *Note TeX or
Metafont failing: (kpathsea)TeX or Metafont failing.

   The files 'trip.diffs', 'mftrap.diffs', and 'mptrap.diffs' in the
'triptrap' directory show the standard diffs against the original
output.  If you diff your diffs against these files, you should come up
clean.  For example
     make trip >&mytrip.diffs
     diff triptrap/trip.diffs mytrip.diffs

   To run the tests separately, use the targets 'trip', 'trap', and
'mptrap'.

   To run simple tests for all the programs as well as the torture
tests, run 'make check'.  You can compare the output to the distributed
file 'tests/check.log' if you like.


File: web2c.info,  Node: Commonalities,  Next: Three programs,  Prev: Installation,  Up: Top

3 Commonalities
***************

Many aspects of the TeX system are the same among more than one program,
so we describe those pieces together, here.

* Menu:

* Option conventions::   - or -, = or ' ' for values.
* Common options::       -help -version -verbose, and TeX/MF/MP options.
* Path searching::       Features of the common path searching library.
* Output file location:: TEXMFOUTPUT allows output in places other than '.'.


File: web2c.info,  Node: Option conventions,  Next: Common options,  Up: Commonalities

3.1 Option conventions
======================

To provide a clean and consistent behavior, we chose to have all these
programs use the GNU function 'getopt_long_only' to parse command lines.
However, we do use in a restricted mode, where all the options have to
come before the rest of the arguments.

   As a result, you can:
   * use '-' or '--' to start an option name;

   * use any unambiguous abbreviation for an option name;

   * separate option names and values with either '=' or one or more
     spaces;

   * use filenames that would otherwise look like options by putting
     them after an option '--'.

   By convention, non-option arguments, if specified, generally define
the name of an input file, as documented for each program.

   If a particular option with a value is given more than once, it is
the last value that counts.

   For example, the following command line specifies the options 'foo',
'bar', and 'verbose'; gives the value 'baz' to the 'abc' option, and the
value 'xyz' to the 'quux' option; and specifies the filename '-myfile-'.

     -foo --bar -verb -abc=baz -quux karl --quux xyz -- -myfile-


File: web2c.info,  Node: Common options,  Next: Path searching,  Prev: Option conventions,  Up: Commonalities

3.2 Common options
==================

All of these programs accept the standard GNU '--help' and '--version'
options, and several programs accept '--verbose'.  Rather than writing
identical descriptions for every program, they are described here.

'--help'
     Print a usage message listing basic usage and all available options
     to standard output, then exit successfully.

'--verbose'
     Print progress reports to standard output.

'--version'
     Print the version number to standard output, then exit
     successfully.

   TeX, Metafont, and MetaPost have a number of additional options in
common:

'-file-line-error'
'-no-file-line-error'
     Change (or do not change) the way error messages are printed.  The
     alternate style looks like error messages from many compilers and
     is easier to parse for some editors that invoke TeX.  This option
     used to be called '-file-line-error-style'.

'-fmt=DUMPNAME'
'-base=DUMPNAME'
'-mem=DUMPNAME'
     Use DUMPNAME instead of the program name or a '%&' line to
     determine the name of the memory dump file read ('fmt' for TeX,
     'base' for Metafont, 'mem' for MetaPost).  *Note Memory dumps::.
     Also sets the program name to DUMPNAME if no '-progname' option was
     given.

'-halt-on-error'
     Stop processing and exit when an error occurs, as opposed to the
     normal process of trying to recover and continue.

'-ini'
     Enable the "initial" form of the program (*note Initial and
     virgin::).  This is implicitly set if the program name is 'initex'
     resp. 'inimf'.

'-interaction=STRING'
     Set the interaction mode from the command line.  The STRING must be
     one of 'batchmode', 'nonstopmode', 'scrollmode', or
     'errorstopmode'.

'-jobname=STRING'
     Set the job name to STRING, instead of deriving it from the name of
     the input file.

'-kpathsea-debug=NUMBER'
     Set path searching debugging flags according to the bits of NUMBER
     (*note (kpathsea)Debugging::).  You can also specify this in
     'KPATHSEA_DEBUG' environment variable (for all Web2c programs).
     (The command line value overrides.)  The most useful value is '-1',
     to get all available output.

'-output-directory=DIRNAME'
     Specify the directory DIRNAME to which output files are written.
     Also look for input files in DIRNAME first, before looking along
     the normal search path.  *Note Output file location::.

'-parse-first-line'
'-no-parse-first-line'
     Check or disable checking whether the first line of the main input
     file starts with '%&', and parse it if it does.  This line can be
     used specify the format and/or a TCX file.

'-progname=STRING'
     Set program (and memory dump) name to STRING.  This may affect the
     search paths and other values used (*note (kpathsea)Config
     files::).  Using this option is equivalent to making a link named
     STRING to the binary and then invoking the binary under that name.
     *Note Memory dumps::.

'-recorder'
     Enable the filename recorder.  This makes the program save a list
     of the opened files into a file with (by default) extension '.fls'.
     For Aleph, this option is always on, and the file has extension
     '.ofl'.

     Ordinarily, the '.fls' file is written to the same location as the
     '.log' file, for example, respecting '-output-directory' if it is
     given (*note Output file location::).  However, if TeX processing
     is done on the command line (or in response to the '**' prompt),
     the '.fls' might be written to the current directory, or include an
     integer (the current pid), as in 'texput1234.fls'.  You can use
     '-jobname' to explicitly set the basename.

'-translate-file=TCXFILE'
     Use TCXFILE to define which characters are printable and
     translations between the internal and external character sets.
     Moreover, TCXFILE can be explicitly declared in the first line of
     the main input file '%& -translate-file=TCXFILE'.  This is the
     recommended method for portability reasons.  *Note TCX files::.

'-8bit'
     This option specifies that by default all characters should be
     considered printable.  If '-translate-file' was given as well, then
     the TCX file may mark characters as non-printable.


File: web2c.info,  Node: Path searching,  Next: Output file location,  Prev: Common options,  Up: Commonalities

3.3 Path searching
==================

All of the Web2c programs, including TeX, which do path searching use
the Kpathsea routines to do so.  The precise names of the environment
and configuration file variables which get searched for particular file
formatted are therefore documented in the Kpathsea manual (*note
(kpathsea)Supported file formats::).  Reading 'texmf.cnf' (*note
(kpathsea)Config files::), invoking 'mktex...' scripts (*note
(kpathsea)mktex scripts::), and so on are all handled by Kpathsea.

   The programs which read fonts make use of another Kpathsea feature:
'texfonts.map', which allows arbitrary aliases for the actual names of
font files; for example, 'Times-Roman' for 'ptmr8r.tfm'.  The
distributed (and installed by default) 'texfonts.map' includes aliases
for many widely available PostScript fonts by their PostScript names.


File: web2c.info,  Node: Output file location,  Prev: Path searching,  Up: Commonalities

3.4 Output file location
========================

All the programs generally follow the usual convention for output files.
Namely, they are placed in the directory current when the program is
run, regardless of any input file location; or, in a few cases, output
is to standard output.

   For example, if you run 'tex /tmp/foo', for example, the output will
be in './foo.dvi' and './foo.log', not '/tmp/foo.dvi' and
'/tmp/foo.log'.

   You can use the '-output-directory' option to cause all output files
that would normally be written in the current directory to be written in
the specified directory instead.  *Note Common options::.

   If the current directory is not writable, and '-output-directory' is
not specified, the main programs (TeX, Metafont, MetaPost, and BibTeX)
make an exception: if the config file or environment variable value
'TEXMFOUTPUT' is set (it is not by default), output files are written to
the directory specified.

   'TEXMFOUTPUT' is also checked for input files, as TeX often generates
files that need to be subsequently read; for input, no suffixes (such as
'.tex') are added by default and no exhaustive path searching is done,
the input name is simply checked as given.


File: web2c.info,  Node: Three programs,  Next: TeX,  Prev: Commonalities,  Up: Top

4 Three programs: Metafont, MetaPost, and TeX
*********************************************

TeX, Metafont, and MetaPost have a number of features in common.
Besides the ones here, command-line options and other commonalities are
described in the previous section.

* Menu:

* Runtime options::             The 'texmf.cnf' configuration file.
* Initial and virgin::          Making memory dumps vs. production runs.
* Memory dumps::                .fmt/.base files for fast startup.
* Editor invocation::           The 'e' response at errors.
* \input filenames::            Filename delimiters and Kpathsea expansion.


File: web2c.info,  Node: Runtime options,  Next: Initial and virgin,  Up: Three programs

4.1 Runtime options
===================

Besides the configure- and compile-time options described in the
installation section (*note Installation::), you can control a number of
parameters in the 'texmf.cnf' runtime file read by Kpathsea (*note
(kpathsea)Config files::).

   The main purpose of 'texmf.cnf' is to specify search paths, but array
sizes and other options are also set there.  Most are rather obscure.
Here are a few of the more interesting values:

'main_memory'
     Total words of memory available, for TeX, Metafont, and MetaPost.
     Must remake the format file after changing.

'extra_mem_bot'
     Extra space for "large" TeX data structures (default 0): boxes,
     glue, breakpoints, et al.  If you use PiCTeX, you may well want to
     set this.

'expand_depth'
     Limit on recursive expansion calls before TeX aborts (default
     10000).  If a TeX program does an unterminated recursive expansion,
     TeX will dutifully expand macros until the system's runtime stack
     overflows, typically with a segmentation fault (SIGSEGV). This
     parameter was introduced to minimize the chance of that unpleasant
     (though not dangerous) crash, instead allowing TeX to quit with a
     more informative message.

     The crash can still happen, though, if the system has an
     exceptionally small memory allocation for its stack.  There is no
     quantitative way to determine the limit, and it does not seem worth
     implementing system-dependent heuristics to guess at the number,
     since it's highly improbable that any real TeX code will ever need
     more than 10000 recursive expansions (it has never happened).  For
     the same reason, using the libsigsegv library
     (<https://gnu.org/s/libsigsegv>) does not seem worth the effort.

'texmf_casefold_search'
     *Note (kpathsea)Casefolding search::.

   Ideally all arrays would be dynamically expanded as necessary, so the
only limiting factor would be the amount of swap space available, or
some configurable limit much larger than can currently be supported.

   Unfortunately, implementing this is extremely difficult, as the fixed
size of arrays is assumed in many places throughout the source code.
These runtime limits are a practical compromise between the compile-time
limits in previous versions, and truly dynamic arrays.  (On the other
hand, the Web2c BibTeX implementation does do true dynamic reallocation
of some arrays.)

   Nowadays there is rarely a reason to modify the values.  But if you
do wish to modify 'texmf.cnf', in TeX Live the best approach is to put
your changes, and only your changes at the top of the TL installation
tree.  That is, if the system 'texmf.cnf' is installed in
'/some/path/to/texlive/YYYY/texmf-dist/web2c/texmf.cnf' is put your
custom settings in '/some/path/to/texlive/YYY/texmf.cnf', where YYYY is
the year of installation (if you use that subdirectory; it's the
default).  That way, unrelated changes to the system 'texmf.cnf' can
happen with normal updates, without affecting your local values.


File: web2c.info,  Node: Initial and virgin,  Next: Memory dumps,  Prev: Runtime options,  Up: Three programs

4.2 Initial and virgin
======================

The TeX and Metafont programs each have two main variants, called
"initial" and "virgin".  MetaPost no longer makes this distinction.

   The initial form is enabled if:
  1. the '-ini' option was specified; or
  2. the program name is 'initex' resp. 'inimf'; or
  3. the first line of the main input file is '%&ini';
otherwise, the virgin form is used.

   The "virgin" form is the one generally invoked for production use.
The first thing it does is read a memory dump (*note Determining the
memory dump to use::), and then proceeds on with the main job.

   The "initial" form is generally used only to create memory dumps (see
the next section).  It starts up more slowly than the virgin form,
because it must do lengthy initializations that are encapsulated in the
memory dump file.


File: web2c.info,  Node: Memory dumps,  Next: Editor invocation,  Prev: Initial and virgin,  Up: Three programs

4.3 Memory dumps
================

In typical use, TeX and Metafont require a large number of macros to be
predefined; therefore, they support "memory dump" files, which can be
read much more efficiently than ordinary source code.

* Menu:

* Creating memory dumps::
* Determining the memory dump to use::
* Hardware and memory dumps::


File: web2c.info,  Node: Creating memory dumps,  Next: Determining the memory dump to use,  Up: Memory dumps

4.3.1 Creating memory dumps
---------------------------

The programs all create memory dumps in slightly idiosyncratic (thought
substantially similar) way, so we describe the details in separate
sections (references below).  The basic idea is to run the initial
version of the program (*note Initial and virgin::), read the source
file to define the macros, and then execute the '\dump' primitive.

   Also, each program uses a different filename extension for its memory
dumps, since although they are completely analogous they are not
interchangeable (TeX cannot read a Metafont memory dump, for example).

   Here is a list of filename extensions with references to examples of
creating memory dumps:

TeX
     ('.fmt') *Note Initial TeX: Initial TeX.

Metafont
     ('.base') *Note Initial Metafont::.

   When making memory dumps, the programs read environment variables and
configuration files for path searching and other values as usual.  If
you are making a new installation and have environment variables
pointing to an old one, for example, you will probably run into
difficulties.


File: web2c.info,  Node: Determining the memory dump to use,  Next: Hardware and memory dumps,  Prev: Creating memory dumps,  Up: Memory dumps

4.3.2 Determining the memory dump to use
----------------------------------------

The virgin form (*note Initial and virgin::) of each program always
reads a memory dump before processing normal source input.  All three
programs determine the memory dump to use in the same way:

  1. If the first non-option command-line argument begins with '&', the
     program uses the remainder of that argument as the memory dump
     name.  For example, running 'tex \&super' reads 'super.fmt'.  (The
     backslash protects the '&' against interpretation by the shell.)

  2. If the '-fmt' resp. '-base' option is specified, its value is used.

  3. If the '-progname' option is specified, its value is used.

  4. If the first line of the main input file (which must be specified
     on the command line, not in response to '**') is '%&DUMP', and DUMP
     is an existing memory dump of the appropriate type, DUMP is used.

     The first line of the main input file can also specify which
     character translation file is to be used:
     '%&-translate-file=TCXFILE' (*note TCX files::).

     These two roles can be combined: '%&DUMP -translate-file=TCXFILE'.
     If this is done, the name of the dump must be given first.

  5. Otherwise, the program uses the program invocation name, most
     commonly 'tex' resp. 'mf'.  For example, if 'latex' is a link to
     'tex', and the user runs 'latex foo', 'latex.fmt' will be used.


File: web2c.info,  Node: Hardware and memory dumps,  Prev: Determining the memory dump to use,  Up: Memory dumps

4.3.3 Hardware and memory dumps
-------------------------------

By default, memory dump files are generally sharable between
architectures of different types; specifically, on machines of different
endianness (*note (libc)Byte order::).  (This is a feature of the Web2c
implementation, and is not true of all TeX implementations.)  If you
specify '--disable-dump-share' to 'configure', however, memory dumps
will be endian-dependent.

   The reason to do this is speed.  To achieve endian-independence, the
reading of memory dumps on LittleEndian architectures, such as PC's and
DEC architectures, is somewhat slowed (all the multibyte values have to
be swapped).  Usually, this is not noticeable, and the advantage of
being able to share memory dumps across all platforms at a site far
outweighs the speed loss.  But if you're installing Web2c for use on
LittleEndian machines only, perhaps on a PC being used only by you, you
may wish to get maximum speed.

   TeXnically, even without '--disable-dump-share', sharing of '.fmt'
files cannot be guaranteed to work.  Floating-point values are always
written in native format, and hence will generally not be readable
across platforms.  Fortunately, TeX uses floating point only to
represent glue ratios, and all common formats (plain, LaTeX, AMSTeX,
...) do not do any glue setting at '.fmt'-creation time.  Metafont does
not use floating point in any dumped value at all.

   Incidentally, different memory dump files will never compare equal
byte-for-byte, because the program always dumps the current date and
time.  So don't be alarmed by just a few bytes difference.

   If you don't know what endianness your machine is, and you're
curious, here is a little C program to tell you.  (The 'configure'
script contains a similar program.)  This is from the book 'C: A
Reference Manual', by Samuel P. Harbison and Guy L. Steele Jr.  (*note
References::).

     main ()
     {
       /* Are we little or big endian?  From Harbison&Steele.  */
       union
       {
         long l;
         char c[sizeof (long)];
       } u;
       u.l = 1;
       if (u.c[0] == 1)
         printf ("LittleEndian\n");
       else if (u.c[sizeof (long) - 1] == 1)
         printf ("BigEndian\n");
       else
         printf ("unknownEndian");

       exit (u.c[sizeof (long) - 1] == 1);
     }


File: web2c.info,  Node: Editor invocation,  Next: \input filenames,  Prev: Memory dumps,  Up: Three programs

4.4 Editor invocation
=====================

TeX, Metafont, and MetaPost all (by default) stop and ask for user
intervention at an error.  If the input came from a file, and the user
responds with 'e' or 'E', the program invokes an editor.

   Specifying '--with-editor=CMD' to 'configure' sets the default editor
command string to CMD.  The environment variables/configuration values
'TEXEDIT', 'MFEDIT', and 'MPEDIT' (respectively) override this.  If
'--with-editor' is not specified, the default is 'vi +%d %s' on Unix,
and an invocation of the TeXworks editor on Windows.  (See 'texmf.cnf'
for the precise values.)

   In this string, '%d' is replaced by the line number of the error, and
'%s' is replaced by the name of the current input file.


File: web2c.info,  Node: \input filenames,  Prev: Editor invocation,  Up: Three programs

4.5 '\input' filenames
======================

TeX, Metafont, and MetaPost source programs can all read other source
files with the '\input' (TeX) and 'input' (MF and MP) primitives:
     \input NAME % in TeX

   The file NAME can always be terminated with whitespace; for Metafont
and MetaPost, the statement terminator ';' also works.  (LaTeX and other
macro packages provide other interfaces to '\input' that allow different
notation; here we are concerned only with the primitive operation.)

   As (allowed) extensions to standard TeX, Web2c also supports
specifying the filename in double quotes ('"some name"') and in braces
('{"some name"}'), which is convenient for filenames containing spaces
or other special characters, as described in the sections below.

   In all cases, space tokens are ignored after the filename is read.

   Also, double quote ('"') characters are ignored within the filename;
there is no way to read files whose names contain a '"'.

   However, for maximal portability of your document across systems, use
only the characters 'a'-'z', '0'-'9', and '.'.  Do not use anything but
simple filenames, since directory separators vary among systems;
instead, add the necessary directories to the appropriate search path.

* Menu:

* Quotes: \input quoted filename.   \input "some name"
* Braces: \input braced filename.   \input {some name}
* Caveats: \input filename caveats. Tokenization, nulls, Kpathsea expansion.


File: web2c.info,  Node: \input quoted filename,  Next: \input braced filename,  Up: \input filenames

4.5.1 '\input' quoted filename: '\input "some name"'
----------------------------------------------------

As of Web2c version 7.5.3 (2004), double-quote characters can be used to
include spaces or other special characters.  In typical use, the '"'
characters surround the entire filename:
     \input "filename with spaces"

   Technically, the quote characters can be used inside the name, and
can enclose any characters, as in:
     \input filename" "with" "spaces

   One more point.  In LaTeX, the quotes are needed inside the braces of
its '\input' macro, thus:
     \input{a b}    % fails
     \input{"a b"}  % ok

   There is no way to quote the quote character.


File: web2c.info,  Node: \input braced filename,  Next: \input filename caveats,  Prev: \input quoted filename,  Up: \input filenames

4.5.2 '\input' braced filename: '\input{some name}'
---------------------------------------------------

As of Web2c 2020, '\input' filenames in TeX engines (this does not apply
in Metafont and MetaPost) can also be specified within a TeX group,
typically curly braces.  For example:
     \input{filename with spaces}

   As always with TeX, the brace characters are not hardwired; what
counts is the category code: the first token after the '\input' must be
of catcode 1 (begin group), and it is matched with the next character of
catcode 2 (end group).

   Within the group-delimited filename, braces are treated as normal
characters.

   As with all forms of filenames, following spaces are ignored (after
the end group), and double quote ('"') characters are ignored within the
filename.


File: web2c.info,  Node: \input filename caveats,  Prev: \input braced filename,  Up: \input filenames

4.5.3 '\input' filename caveats
-------------------------------

The quoting mechanisms just described come into play _after_ TeX has
tokenized and expanded the input.  So, multiple spaces and tabs will
generally be seen as a single space, active characters such as '~' are
expanded first (generally causing an error), and so on.  More examples
below.

   On the other hand, various C library routines and Unix itself use the
null byte (character code zero, ASCII NUL) to terminate strings.  So
filenames in Web2c cannot contain nulls, even though TeX itself does not
treat NUL specially.

   Finally, the present Web2c implementation does '~' and '$' expansion
on NAME, unlike Knuth's original implementation.  Thus:
     \input ~jsmith/$foo.bar
   will dereference the environment variable or Kpathsea config file
value 'foo' and read that file, extended with '.bar', in user 'jsmith''s
home directory.  You can also use braces in the variable expansion, as
in '${foo}bar', if you want to follow the variable name with a letter,
numeral, or '_'.

   (So another way to get a program to read a filename containing
whitespace is to define an environment variable and dereference it.)

   In all the common TeX formats (plain TeX, LaTeX, ConTeXt, AMSTeX,
...), the characters '~' and '$' have special category codes, so to
actually use these in a document you have to change their catcodes or
use '\string'.


File: web2c.info,  Node: TeX,  Next: Metafont,  Prev: Three programs,  Up: Top

5 TeX: Typesetting
******************

TeX is a typesetting system: it was especially designed to handle
complex mathematics, as well as most ordinary text typesetting.

   TeX is a batch language, like C or Pascal, and not an interactive
"word processor": you compile a TeX input file into a corresponding
device-independent (DVI) file (and then translate the DVI file to the
commands for a particular output device).  This approach has both
considerable disadvantages and considerable advantages.  For a complete
description of the TeX language, see 'The TeXbook' (*note References::).
Many other books on TeX, introductory and otherwise, are available.

* Menu:

* tex invocation::              Invoking TeX.
* Initial TeX::                 Making format files.
* Formats::                     Major TeX macro packages.
* Languages and hyphenation::   TeX supports many human languages.
* Shell escapes::               Running subprograms from TeX.
* IPC and TeX::                 DVI output to a socket.
* TeX extensions::              Changes to the TeX language.


File: web2c.info,  Node: tex invocation,  Next: Initial TeX,  Up: TeX

5.1 'tex' invocation
====================

TeX (usually invoked as 'tex') formats the given text and commands, and
outputs a corresponding device-independent representation of the typeset
document.  This section merely describes the options available in the
Web2c implementation.  For a complete description of the TeX typesetting
language, see 'The TeXbook' (*note References::).

   TeX, Metafont, and MetaPost process the command line (described here)
and determine their memory dump (fmt) file in the same way (*note Memory
dumps::).  Synopses:

     tex [OPTION]... [TEXNAME[.tex]] [TEX-COMMANDS]
     tex [OPTION]... \FIRST-LINE
     tex [OPTION]... &FMT ARGS

   TeX searches the usual places for the main input file TEXNAME (*note
(kpathsea)Supported file formats::), extending TEXNAME with '.tex' if
necessary.  To see all the relevant paths, set the environment variable
'KPATHSEA_DEBUG' to '-1' before running the program.

   After TEXNAME is read, TeX processes any remaining TEX-COMMANDS on
the command line as regular TeX input.  Also, if the first non-option
argument begins with a TeX escape character (usually '\'), TeX processes
all non-option command-line arguments as a line of regular TeX input.

   If no arguments or options are specified, TeX prompts for an input
file name with '**'.

   TeX writes the main DVI output to the file 'BASETEXNAME.dvi', where
BASETEXNAME is the basename of TEXNAME, or 'texput' if no input file was
specified.  A DVI file is a device-independent binary representation of
your TeX document.  The idea is that after running TeX, you translate
the DVI file using a separate program to the commands for a particular
output device, such as a PostScript printer (*note Introduction:
(dvips)Top.) or an X Window System display (see xdvi(1)).

   TeX also reads TFM files for any fonts you load in your document with
the '\font' primitive.  By default, it runs an external program named
'mktextfm' to create any nonexistent TFM files.  You can disable this at
configure-time or runtime (*note (kpathsea)mktex configuration::).  This
is enabled mostly for the sake of the EC fonts, which can be generated
at any size.

   TeX can write output files, via the '\openout' primitive; this opens
a security hole vulnerable to Trojan horse attack: an unwitting user
could run a TeX program that overwrites, say, '~/.rhosts'.  (MetaPost
has a 'write' primitive with similar implications).  To alleviate this
and similar problems the functions 'kpathsea_out_name_ok' and
'kpathsea_in_name_ok' from the Kpathse library (*note (kpathsea)Calling
sequence::) are used to determine if a given filename is acceptable to
be opened for output or input, depending on the setting of the
configuration variables 'openout_any' and 'openin_any': 'a' (for "any",
the default for 'openin_any'), 'r' (for "restricted"), or 'p' (for
"paranoid", the default for 'openout_any').

   In any case, all '\openout' filenames are recorded in the log file,
except those opened on the first line of input, which is processed when
the log file has not yet been opened.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-enc'
'-[no]-file-line-error'
'-fmt=FMTNAME'
'-halt-on-error'
'-ini'
'-interaction=STRING'
'-ipc'
'-ipc-start'
'-jobname=STRING'
'-kpathsea-debug=NUMBER'
'-[no]parse-first-line'
'-output-directory'
'-progname=STRING'
'-recorder'
'-translate-file=TCXFILE'
'-8bit'
     These options are common to TeX, Metafont, and MetaPost.  *Note
     Common options::.

'-enc'
     Enable encTeX extensions, such as '\mubyte'.  This can be used to
     support Unicode UTF-8 input encoding.  See
     <http://www.olsak.net/enctex.html>.

'-ipc'
'-ipc-start'
     With either option, TeX writes its DVI output to a socket as well
     as to the usual '.dvi' file.  With '-ipc-start', TeX also opens a
     server program at the other end to read the output.  *Note IPC and
     TeX: IPC and TeX.

     These options are available only if the '--enable-ipc' option was
     specified to 'configure' during installation of Web2c.

'-mktex=FILETYPE'
'-no-mktex=FILETYPE'
     Turn on or off the 'mktex' script associated with FILETYPE.  For
     TeX proper, FILETYPE can only be 'tex' and 'tfm', but for pdfTeX
     and luaTeX, it can also be 'pk'.

'-mltex'
     If we are 'INITEX' (*note Initial and virgin::), enable MLTeX
     extensions such as '\charsubdef'.  Implicitly set if the program
     name is 'mltex'.  *Note MLTeX: MLTeX.

'-output-comment=STRING'
     Use STRING as the DVI file comment.  Ordinarily, this comment
     records the date and time of the TeX run, but if you are doing
     regression testing, you may not want the DVI file to have this
     spurious difference.  This is also taken from the environment
     variable and config file value 'output_comment'.

'-shell-escape'
'-no-shell-escape'
'-shell-restricted'
     Enable, or disable, or enable with restrictions the
     '\write18{SHELL-COMMAND}' feature for external executing shell
     commands.  *Note Shell escapes::.

'-enable-write18'
'-disable-write18'
     Synonyms for '-shell-escape' and '-no-shell-escape', for
     compatibility with MiKTeX.  (MiKTeX also accepts both pairs of
     options.)  *Note Shell escapes::.

'-src-specials'
'-src-specials=STRING'
     This option makes TeX output specific source information using
     '\special' commands in the DVI file.  These '\special' track the
     current file name and line number.

     Using the first form of this option, the '\special' commands are
     inserted automatically.

     In the second form of the option, STRING is a comma separated list
     of the following values: 'cr', 'display', 'hbox', 'math', 'par',
     'parend', 'vbox'.  You can use this list to specify where you want
     TeX to output such commands.  For example, '-src-specials=cr,math'
     will output source information every line and every math formula.

     These commands can be used with the appropriate DVI viewer and text
     editor to switch from the current position in the editor to the
     same position in the viewer and back from the viewer to the editor.

     This option works by inserting '\special' commands into the token
     stream, and thus in principle these additional tokens can be
     recovered or seen by the tricky-enough macros.  If you run across a
     case, let us know, because this counts as a bug.  However, such
     bugs are very hard to fix, requiring significant changes to TeX, so
     please don't count on it.

     Redefining '\special' will not affect the functioning of this
     option.  The commands inserted into the token stream are hard-coded
     to always use the '\special' primitive.

     TeX does not pass the trip test when this option is enabled.


File: web2c.info,  Node: Initial TeX,  Next: Formats,  Prev: tex invocation,  Up: TeX

5.2 Initial TeX
===============

The "initial" form of TeX is invoked by 'tex -ini'.  It does lengthy
initializations avoided by the "virgin" ('vir') form, so as to be
capable of dumping '.fmt' files (*note Memory dumps::).  For a detailed
comparison of virgin and initial forms, *note Initial and virgin::.

   For a list of options and other information, *note tex invocation::.

   Unlike Metafont and MetaPost, many format files are commonly used
with TeX.  The standard one implementing the features described in the
'TeXbook' is 'plain.fmt', also known as 'tex.fmt' (again, *note Memory
dumps::).  It is created by default during installation, but you can
also do so by hand if necessary (e.g., if an update to 'plain.tex' is
issued):
     tex -ini '\input plain \dump'
(The quotes prevent interpretation of the backslashes from the shell.)
Then install the resulting 'plain.fmt' in '$(fmtdir)'
('/usr/local/share/texmf/web2c' by default), and link 'tex.fmt' to it.

   The necessary invocation for generating a format file differs for
each format, so instructions that come with the format should explain.
The top-level 'web2c' Makefile has targets for making most common
formats: plain latex amstex texinfo eplain.  *Note Formats::, for more
details on TeX formats.


File: web2c.info,  Node: Formats,  Next: Languages and hyphenation,  Prev: Initial TeX,  Up: TeX

5.3 Formats
===========

TeX "formats" are large collections of macros, often dumped into a
'.fmt' file (*note Memory dumps::) by 'tex -ini' (*note Initial TeX::).
A number of formats are in reasonably widespread use, and the Web2c
Makefile has targets to make the versions current at the time of
release.  You can change which formats are automatically built by
setting the 'fmts' Make variable; by default, only the 'plain' and
'latex' formats are made.

   You can get the latest versions of most of these formats from the
CTAN archives in subdirectories of 'CTAN:/macros' (for CTAN info, *note
(kpathsea)unixtex.ftp::).  The archive
<ftp://ftp.tug.org/tex/lib.tar.gz> (also available from CTAN) contains
most of these formats (although perhaps not the absolute latest
version), among other things.

latex
     The most widely used format.  The current release is named 'LaTeX
     2e'; new versions are released approximately every six months, with
     patches issued as needed.  The old release was called 'LaTeX 2.09',
     and is no longer maintained or supported.  LaTeX attempts to
     provide generic markup instructions, such as "emphasize", instead
     of specific typesetting instructions, such as "use the 10pt
     Computer Modern italic font".  The LaTeX home page:
     <http://www.latex-project.org>.

context
     ConTeXt is an independent macro package which has a basic document
     structuring approach similar to LaTeX.  It also supports creating
     interactive PDF files and has integrated MetaPost support, among
     many other interesting features.  The ConTeXt home page:
     <http://www.pragma-ade.com>.

amstex
     The official typesetting system of the American Mathematical
     Society.  Like LaTeX, it encourages generic markup commands.  The
     AMS also provides many LaTeX package for authors who prefer LaTeX.
     Taken together, they are used to produce nearly all AMS
     publications, e.g., 'Mathematical Reviews'.  The AMSTeX home page:
     <http://www.ams.org/tex>.

texinfo
     The documentation system developed and maintained by the Free
     Software Foundation for their software manuals.  It can be
     automatically converted into plain text, a machine-readable on-line
     format called 'info', HTML, etc.  The Texinfo home page:
     <http://www.gnu.org/software/texinfo>.

eplain
     The "expanded plain" format provides various common features (e.g.,
     symbolic cross-referencing, tables of contents, indexing, citations
     using BibTeX), for those authors who prefer to handle their own
     high-level formatting.  The Eplain home page:
     <http://www.tug.org/eplain>.

slitex
     An obsolete LaTeX 2.09 format for making slides.  It is replaced by
     the 'slides' document class, along with the 'beamer', 'texpower',
     and other packages.


File: web2c.info,  Node: Languages and hyphenation,  Next: Shell escapes,  Prev: Formats,  Up: TeX

5.4 Languages and hyphenation
=============================

TeX supports most natural languages.  See also *note TeX extensions: TeX
extensions.

* Menu:

* MLTeX::                Multi-lingual TeX.
* TCX files::            Support for different character sets & fonts.
* patgen invocation::    Creating hyphenation patterns.


File: web2c.info,  Node: MLTeX,  Next: TCX files,  Up: Languages and hyphenation

5.4.1 MLTeX: Multi-lingual TeX
------------------------------

Multi-lingual TeX ('mltex') is an extension of TeX originally written by
Michael Ferguson and now updated and maintained by Bernd Raichle.  With
the advent of Unicode, it has become obsolete, though it is still
supported in Web2c in the event of bugs or compilation bugs.

   MLTeX allows the use of non-existing glyphs in a font by declaring
glyph substitutions.  These are restricted to substitutions of an
accented character glyph, which need not be defined in the current font,
by its appropriate '\accent' construction using a base and accent
character glyph, which do have to exist in the current font.  This
substitution is automatically done behind the scenes, if necessary, and
thus MLTeX additionally supports hyphenation of words containing an
accented character glyph for fonts missing this glyph (e.g., Computer
Modern).  Standard TeX suppresses hyphenation in this case.

   MLTeX works at '.fmt'-creation time: the basic idea is to specify the
'-mltex' option to TeX when you '\dump' a format.  Then, when you
subsequently invoke TeX and read that '.fmt' file, the MLTeX features
described below will be enabled.

   Generally, you use special macro files to create an MLTeX '.fmt'
file.

   The sections below describe the two new primitives that MLTeX
defines.  Aside from these, MLTeX is completely compatible with standard
TeX.

* Menu:

* \charsubdef::                 Character substitution definitions.
* \tracingcharsubdef::          Tracing substitutions.


File: web2c.info,  Node: \charsubdef,  Next: \tracingcharsubdef,  Up: MLTeX

5.4.1.1 '\charsubdef': Character substitutions
..............................................

The most important primitive MLTeX adds is '\charsubdef', used in a way
reminiscent of '\chardef':
     \charsubdef COMPOSITE [=] ACCENT BASE

   Each of COMPOSITE, ACCENT, and BASE are font glyph numbers, expressed
in the usual TeX syntax: `\e symbolically, '145 for octal, "65 for hex,
101 for decimal.

   MLTeX's '\charsubdef' declares how to construct an accented character
glyph (not necessarily existing in the current font) using two character
glyphs (that do exist).  Thus it defines whether a character glyph code,
either typed as a single character or using the '\char' primitive, will
be mapped to a font glyph or to an '\accent' glyph construction.

   For example, if you assume glyph code 138 (decimal) for an
e-circumflex and you are using the Computer Modern fonts, which have the
circumflex accent in position 18 and lowercase 'e' in the usual ASCII
position 101 decimal, you would use '\charsubdef' as follows:

     \charsubdef 138 = 18 101

   For the plain TeX format to make use of this substitution, you have
to redefine the circumflex accent macro '\^' in such a way that if its
argument is character 'e' the expansion '\char138 ' is used instead of
'\accent18 e'.  Similar '\charsubdef' declaration and macro
redefinitions have to be done for all other accented characters.

   To disable a previous '\charsubdef C', redefine C as a pair of zeros.
For example:
     \charsubdef '321 = 0 0  % disable N tilde
(Octal '321 is the ISO Latin-1 value for the Spanish N tilde.)

   '\charsubdef' commands should only be given once.  Although in
principle you can use '\charsubdef' at any time, the result is
unspecified.  If '\charsubdef' declarations are changed, usually either
incorrect character dimensions will be used or MLTeX will output missing
character warnings.  (The substitution of a '\charsubdef' is used by TeX
when appending the character node to the current horizontal list, to
compute the width of a horizontal box when the box gets packed, and when
building the '\accent' construction at '\shipout'-time.  In summary, the
substitution is accessed often, so changing it is not desirable, nor
generally useful.)


File: web2c.info,  Node: \tracingcharsubdef,  Prev: \charsubdef,  Up: MLTeX

5.4.1.2 '\tracingcharsubdef': Substitution diagnostics
......................................................

To help diagnose problems with '\charsubdef', MLTeX provides a new
primitive parameter, '\tracingcharsubdef'.  If positive, every use of
'\charsubdef' will be reported.  This can help track down when a
character is redefined.

   In addition, if the TeX parameter '\tracinglostchars' is 100 or more,
the character substitutions actually performed at '\shipout'-time will
be recorded.


File: web2c.info,  Node: TCX files,  Next: patgen invocation,  Prev: MLTeX,  Up: Languages and hyphenation

5.4.2 TCX files: Character translations
---------------------------------------

TCX (TeX character translation) files help TeX support direct input of
8-bit international characters if fonts containing those characters are
being used.  Specifically, they map an input (keyboard) character code
to the internal TeX character code (a superset of ASCII).

   Of the various proposals for handling more than one input encoding,
TCX files were chosen because they follow Knuth's original ideas for the
use of the 'xchr' and 'xord' tables.  He ventured that these would be
changed in the WEB source in order to adjust the actual version to a
given environment.  It turns out, however, that recompiling the WEB
sources is not as simple a task as Knuth may have imagined; therefore,
TCX files, providing the possibility of changing of the conversion
tables on on-the-fly, have been implemented instead.

   This approach limits the portability of TeX documents, as some
implementations do not support it (or use a different method for
input-internal reencoding).  It may also be problematic to determine the
encoding to use for a TeX document of unknown provenance; in the worst
case, failure to do so correctly may result in subtle errors in the
typeset output.  But we feel the benefits outweigh these disadvantages.

   This is entirely independent of the MLTeX extension (*note MLTeX::):
whereas a TCX file defines how an input keyboard character is mapped to
TeX's internal code, MLTeX defines substitutions for a non-existing
character glyph in a font with a '\accent' construction made out of two
separate character glyphs.  TCX files involve no new primitives; it is
not possible to specify that an input (keyboard) character maps to more
than one character.

   Information on specifying TCX files:

   * The best way to specify a TCX file is to list it explicitly in the
     first line of the main document:
          %& -translate-file=TCXFILE

   * You can also specify a TCX file to be used on a particular TeX run
     with the command-line option '-translate-file=TCXFILE'.

   * TCX files are searched for along the 'WEB2C' path.

   * Initial TeX (*note Initial TeX: Initial TeX.) ignores TCX files.

   The Web2c distribution comes with a number of TCX files.  Two
important ones are 'il1-t1.tcx' and 'il2-t1.tcx', which support ISO
Latin 1 and ISO Latin 2, respectively, with Cork-encoded fonts
(a.k.a. the LaTeX T1 encoding).  TCX files for Czech, Polish, and Slovak
are also provided.

   One other notable TCX file is 'empty.tcx', which is, well, empty.
Its purpose is to reset Web2C's behavior to the default (only visible
ASCII being printable, as described below) when a format was dumped with
another TCX being active--which is in fact the case for everything but
plain TeX in the TeX Live and other distributions.  Thus:

     latex somefile8.tex
     => terminal etc. output with 8-bit chars
     latex --translate-file=empty.tcx somefile8.tex
     => terminal etc. output with ^^ notation

   Syntax of TCX files:
  1. Line-oriented.  Blank lines are ignored.

  2. Whitespace is ignored except as a separator.

  3. Comments start with '%' and continue to the end of the line.

  4. Otherwise, a line consists of one or two character codes,
     optionally followed by 0 or 1.  The last number indicates whether
     DEST is considered printable.
          SRC [DEST [PRNT]]

  5. Each character code may be specified in octal with a leading '0',
     hexadecimal with a leading '0x', or decimal otherwise.  Values must
     be between 0 and 255, inclusive (decimal).

  6. If the DEST code is not specified, it is taken to be the same as
     SRC.

  7. If the same SRC code is specified more than once, it is the last
     definition that counts.

   Finally, here's what happens: when TeX sees an input character with
code SRC, it 1) changes SRC to DEST; and 2) makes the DEST code
"printable", i.e., printed as-is in diagnostics and the log file rather
than in '^^' notation.

   By default, no characters are translated, and character codes between
32 and 126 inclusive (decimal) are printable.

   Specifying translations for the printable ASCII characters (codes
32-127) will yield unpredictable results.  Additionally you shouldn't
make the following characters printable: '^^I' (TAB), '^^J' (line feed),
'^^M' (carriage return), and '^^?' (delete), since TeX uses them in
various ways.

   Thus, the idea is to specify the input (keyboard) character code for
SRC, and the output (font) character code for DEST.

   By default, only the printable ASCII characters are considered
printable by TeX.  If you specify the '-8bit' option, all characters are
considered printable by default.  If you specify both the '-8bit' option
and a TCX file, then the TCX can set specific characters to be
non-printable.

   Both the specified TCX encoding and whether characters are printable
are saved in the dump files (like 'tex.fmt').  So by giving these
options in combination with '-ini', you control the defaults seen by
anyone who uses the resulting dump file.

   When loading a dump, if the '-8bit' option was given, then all
characters become printable by default.

   When loading a dump, if a TCX file was specified, then the TCX data
from the dump is ignored and the data from the file used instead.


File: web2c.info,  Node: patgen invocation,  Prev: TCX files,  Up: Languages and hyphenation

5.4.3 Patgen: Creating hyphenation patterns
-------------------------------------------

Patgen creates hyphenation patterns from dictionary files for use with
TeX.  Synopsis:

     patgen DICTIONARY PATTERNS OUTPUT TRANSLATE

   Each argument is a filename.  No path searching is done.  The output
is written to the file OUTPUT.

   In addition, Patgen prompts interactively for other values.

   For more information, see 'Word hy-phen-a-tion by com-puter' by Frank
Liang (*note References::), and also the 'patgen.web' source file.

   The only options are '-help' and '-version' (*note Common options::).


File: web2c.info,  Node: Shell escapes,  Next: IPC and TeX,  Prev: Languages and hyphenation,  Up: TeX

5.5 Shell escapes
=================

TeX can execute "shell escapes", that is, arbitrary shell commands.
Although tremendously useful, this also has obvious security
implications.  Therefore, as of TeX Live 2009, a "restricted" mode for
shell escapes is the default mode of operation, which allows executing
only certain commands, as specified in the 'texmf.cnf' configuration
file.

   * Unrestricted shell escapes are allowed if the option
     '--shell-escape' is specified, or if the environment variable or
     config file value 'shell_escape' is set to 't' or 'y' and '1'.

   * Restricted shell escapes are allowed if 'shell_escape' is set to
     'p'.  This is the default.

   * Shell escapes are completely disabled if '--no-shell-escape' is
     specified, or if 'shell_escape' is set to anything else.

   When enabled, the TeX construct to execute a system command is
'\write18{SHELL-COMMAND}'; for example:

     \write18{echo "hello, world"}

   From TeX's point of view, this is a normal '\write' command, and is
therefore subject to the usual TeX expansions.  Also, the system call
either happens during the '\output' routine or right away, according to
the absence or presence of the '\immediate' prefix, as usual for
'\write'.

   The SHELL-COMMAND string is passed to the command shell (via the C
library function 'system').  The output of SHELL-COMMAND is not diverted
anywhere, so it will not appear in the log file, or anywhere but the
terminal output.  The exit status of the system call is also not
available to TeX.

   In unrestricted mode, the argument is simply passed straight to
'system' unaltered.

   In restricted mode, ASCII double quote characters (") should always
be used in the argument to '\write18' where quoting of arguments is
needed, as in the example above.  This is to achieve some measure of
system independence.  On Unix systems, these are replaced with single
quote (') characters to avoid insecure further expansion.  Care is also
taken on Windows to avoid additional expansions (from, e.g., `...`).
Mismatched quotation marks in the command string result in a diagnostic
message in the log file; no execution is performed.

   After quotation processing, if the first word (delimited by a space
or tab) of the command is in the list specified by the
'shell_escape_commands' configuration value, the command is executed.
Otherwise it is not.  In any case, a message is written to the log file.

   The 'shell_escape_commands' value is a comma-separated list of words.
Whitespace is significant, and typically should not be present.  The
default definition in 'texmf.cnf' looks like this, but with more
commands included:

     shell_escape_commands = bibtex,kpsewhich,repstopdf,...

   pdfTeX and luaTeX support reading (via '\input' and '\openin') and
writing (via '\openout') from pipes if the first character is '|'.  The
following command is then treated exactly the same as the argument to
'\write18'.  In these engines, the primitive variable '\pdfshellescape'
is set to 0 if shell escapes are disabled, 1 if they are enabled, and 2
if they are enabled with restrictions.

   The purpose of this feature is to make it possible for TeX documents
to perform useful external actions in the common case of an individual
user running a known document on his or her own machine.  In such
environments as CGI scripts or wikis where the input has to be
considered untrustworthy, shell escapes should be completely disabled.


File: web2c.info,  Node: IPC and TeX,  Next: TeX extensions,  Prev: Shell escapes,  Up: TeX

5.6 IPC and TeX
===============

(If anyone uses this feature and needs documentation, write
<tex-k@tug.org>.)

   This functionality is available only if the '--enable-ipc' option was
specified to 'configure' during installation of Web2c (*note
Installation::).

   If you define 'IPC_DEBUG' before compilation (e.g., with 'make
XCFLAGS=-DIPC_DEBUG'), TeX will print messages to standard error about
its socket operations.  This may be helpful if you are, well, debugging.


File: web2c.info,  Node: TeX extensions,  Prev: IPC and TeX,  Up: TeX

5.7 TeX extensions
==================

The base TeX program has been extended in many ways.  Here's a partial
list.

e-TeX
     Adds many new primitives, including right-to-left typesetting and
     more registers.  Now frozen.  More info:
     <https://ctan.org/pkg/etex>.

Aleph
     This adds Unicode support, right-to-left typesetting, and more.
     Omega was the original program.  Aleph is an updated version with a
     variety of bug fixes, and includes e-TeX.  Aleph is not actively
     maintained.  More info: <https://ctan.org/pkg/aleph>,
     <https://ctan.org/pkg/omega>.

pdfTeX
     Can produce PDF as well as DVI files.  It also incorporates the
     e-TeX extensions, new primitives for hypertext and
     micro-typography, reading/writing from pipes, and much more.  Home
     page: <http://pdftex.org>.

LuaTeX
     Embeds the Lua programming language (<http://lua.org>) and opens up
     the TeX typesetting engine to control from Lua.  Also supports
     Unicode input and OpenType- and system fonts.  Home page:
     <http://luatex.org>.

XeTeX
     Combines support for Unicode input and OpenType- and system fonts
     with the capabilities of pdfTeX.  Home page:
     <https://tug.org/xetex>.

pTeX
upTeX
     With additional support for Japanese; pTeX was the original engine,
     and upTeX has native Unicode support and thus is more useful for
     Chinese and Korean.  More info: <https://ctan.org/pkg/ptex>,
     <https://ctan.org/pkg/uptex>.


File: web2c.info,  Node: Metafont,  Next: MetaPost,  Prev: TeX,  Up: Top

6 Metafont: Creating typeface families
**************************************

Metafont is a system for producing shapes; it was designed for producing
complete typeface families, but it can also produce geometric designs,
dingbats, etc.  And it has considerable mathematical and
equation-solving capabilities which can be useful entirely on their own.

   Metafont is a batch language, like C or Pascal: you compile a
Metafont program into a corresponding font, rather than interactively
drawing lines or curves.  This approach has both considerable
disadvantages (people unfamiliar with conventional programming languages
will be unlikely to find it usable) and considerable advantages (you can
make your design intentions specific and parameterizable).  For a
complete description of the Metafont language, see 'The METAFONTbook'
(*note References::).

* Menu:

* mf invocation::               Invoking Metafont.
* Initial Metafont::            Making bases.
* Modes::                       Device definitions for Metafont.
* Online Metafont graphics::    Seeing MF output online.
* gftodvi invocation::          Making proofsheets for fonts.
* mft invocation::              Prettyprinting Metafont sources.


File: web2c.info,  Node: mf invocation,  Next: Initial Metafont,  Up: Metafont

6.1 'mf' invocation
===================

Metafont (usually invoked as 'mf') reads character definitions specified
in the Metafont programming language, and outputs the corresponding
font.  This section merely describes the options available in the Web2c
implementation.  For a complete description of the Metafont language,
see 'The Metafontbook' (*note References::).

   Metafont processes its command line and determines its memory dump
(base) file in a way exactly analogous to MetaPost and TeX (*note tex
invocation::, and *note Memory dumps::).  Synopses:

     mf [OPTION]... [MFNAME[.mf]] [MF-COMMANDS]
     mf [OPTION]... \FIRST-LINE
     mf [OPTION]... &BASE ARGS

   Most commonly, a Metafont invocation looks like this:
     mf '\mode:=MODE; mag:=MAGNIFICATION; input MFNAME'
(The single quotes avoid unwanted interpretation by the shell.)

   Metafont searches the usual places for the main input file MFNAME
(*note (kpathsea)Supported file formats::), extending MFNAME with '.mf'
if necessary.  To see all the relevant paths, set the environment
variable 'KPATHSEA_DEBUG' to '-1' before running the program.  By
default, Metafont runs an external program named 'mktexmf' to create any
nonexistent Metafont source files you input.  You can disable this at
configure-time or runtime (*note (kpathsea)mktex configuration::).  This
is mostly for the sake of the EC fonts, which can be generated at any
size.

   Metafont writes the main GF output to the file 'BASEMFNAME.NNNgf',
where NNN is the font resolution in pixels per inch, and BASEMFNAME is
the basename of MFNAME, or 'mfput' if no input file was specified.  A GF
file contains bitmaps of the actual character shapes.  Usually GF files
are converted immediately to PK files with GFtoPK (*note gftopk
invocation::), since PK files contain equivalent information, but are
more compact.  (Metafont output in GF format rather than PK for only
historical reasons.)

   Metafont also usually writes a metric file in TFM format to
'BASEMFNAME.tfm'.  A TFM file contains character dimensions, kerns, and
ligatures, and spacing parameters.  TeX reads only this .tfm file, not
the GF file.

   The MODE in the example command above is a name referring to a device
definition (*note Modes::); for example, 'localfont' or 'ljfour'.  These
device definitions must generally be precompiled into the base file.  If
you leave this out, the default is 'proof' mode, as stated in 'The
Metafontbook', in which Metafont outputs at a resolution of 2602dpi;
this is usually not what you want.  The remedy is simply to assign a
different mode--'localfont', for example.

   The MAGNIFICATION assignment in the example command above is a
magnification factor; for example, if the device is 600dpi and you
specify 'mag:=2', Metafont will produce output at 1200dpi.  Very often,
the MAGNIFICATION is an expression such as 'magstep(.5)', corresponding
to a TeX "magstep", which are factors of 1.2 * sqrt(2).

   After running Metafont, you can use the font in a TeX document as
usual.  For example:
     \font\myfont = newfont
     \myfont Now I am typesetting in my new font (minimum hamburgers).

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-[no]-file-line-error'
'-fmt=FMTNAME'
'-halt-on-error'
'-ini'
'-interaction=STRING'
'-jobname=STRING'
'-kpathsea-debug=NUMBER'
'-[no]parse-first-line'
'-output-directory'
'-progname=STRING'
'-recorder'
'-translate-file=TCXFILE'
'-8bit'
     These options are common to TeX, Metafont, and MetaPost.  *Note
     Common options::.

'-mktex=FILETYPE'
'-no-mktex=FILETYPE'
     Turn on or off the 'mktex' script associated with FILETYPE.  The
     only value that makes sense for FILETYPE is 'mf'.


File: web2c.info,  Node: Initial Metafont,  Next: Modes,  Prev: mf invocation,  Up: Metafont

6.2 Initial Metafont
====================

'inimf' is the "initial" form of Metafont, which does lengthy
initializations avoided by the "virgin" ('vir') form, so as to be
capable of dumping '.base' files (*note Memory dumps::).  For a detailed
comparison of virgin and initial forms, see *note Initial and virgin::.

   For a list of options and other information, see *note mf
invocation::.

   The only memory dump file commonly used with Metafont is the default
'plain.base', also known as 'mf.base' (again, *note Memory dumps::).  It
is created by default during installation, but you can also do so by
hand if necessary (e.g., if a Metafont update is issued):
     mf -ini '\input plain; input modes; dump'
(The quotes prevent interpretation of the backslashes from the shell.)
Then install the resulting 'plain.base' in '$(basedir)'
('/usr/local/share/texmf/web2c' by default), and link 'mf.base' to it.

   For an explanation of the additional 'modes.mf' file, see *note
Modes::.  This file has no counterpart in TeX or MetaPost.

   In the past, it was sometimes useful to create a base file
'cmmf.base' (a.k.a. 'cm.base'), with the Computer Modern macros also
included in the base file.  Nowadays, however, the additional time
required to read 'cmbase.mf' is exceedingly small, usually not enough to
be worth the administrative hassle of updating the 'cmmf.base' file when
you install a new version of 'modes.mf'.  People actually working on a
typeface may still find it worthwhile to create their own base file, of
course.


File: web2c.info,  Node: Modes,  Next: Online Metafont graphics,  Prev: Initial Metafont,  Up: Metafont

6.3 Modes: Device definitions for Metafont
==========================================

Running Metafont and creating Metafont base files requires information
that TeX and MetaPost do not: "mode" definitions which specify device
characteristics, so Metafont can properly rasterize the shapes.

   When making a base file, a file containing modes for
locally-available devices should be input after 'plain.mf'.  One
commonly used file is <ftp://ftp.tug.org/tex/modes.mf>; it includes all
known definitions.

   If, however, for some reason you have decreased the memory available
in your Metafont, you may need to copy 'modes.mf' and remove the
definitions irrelevant to you (probably most of them) instead of using
it directly.  (Or, if you're a Metafont hacker, maybe you can suggest a
way to redefine 'mode_def' and/or 'mode_setup'; right now, the amount of
memory used is approximately four times the total length of the
'mode_def' names, and that's a lot.)

   If you have a device not included in 'modes.mf', please see comments
in that file for how to create the new definition, and please send the
definition to <tex-fonts@math.utah.edu> to get it included in the next
release of 'modes.mf'.

   Usually, when you run Metafont you must supply the name of a mode
that was dumped in the base file.  But you can also define the mode
characteristics dynamically, by invoking Metafont with an assignment to
'smode' instead of 'mode', like this:
     mf '\smode:="newmode.mf"; mag:=MAGNIFICATION; input MFNAME'
This is most useful when you are working on the definition of a new
mode.

   The MAGNIFICATION and MFNAME arguments are explained in *note mf
invocation::.  In the file 'newmode.mf', you should have the following
(with no 'mode_def' or 'enddef'), if you are using 'modes.mf'
conventions:
     mode_param (pixels_per_inch, DPI);
     mode_param (blacker, B);
     mode_param (fillin, F);
     mode_param (o_correction, O);
     mode_common_setup_;
(Of course, you should use real numbers for DPI, B, F, and O.)

   For more information on the use of 'smode', or if you are not using
'modes.mf', see page 269 of 'The Metafontbook'.


File: web2c.info,  Node: Online Metafont graphics,  Next: gftodvi invocation,  Prev: Modes,  Up: Metafont

6.4 Online Metafont graphics
============================

The Web2c implementation of Metafont can do online graphics with a
number of devices.  (See the Metafont manual for more information about
how to draw on your screen.)  By default, no graphics support is
enabled.

   Metafont examines the 'MFTERM' environment variable or config file
value at runtime, or the 'TERM' environment variable if 'MFTERM' is not
set, to determine the device support to use.  Naturally, only the
devices for which support has been compiled in can be selected.

   Here is a table of the possibilities, showing the 'MFTERM' value and
the corresponding 'configure' option(s) in parentheses.

'epsf'
     ('--enable-epsfwin') Pseudo-window server for Encapsulated
     PostScript (see 'web2c/window/epsf.c').  This device produces an
     EPS file containing the graphics which would be displayed online on
     other devices.  The name of the EPS file defaults to metafont.eps
     but can be changed by setting the MFEPSF environment variable to
     the new filename.  Contributed by Mathias Herberts.

'hp2627'
     ('--enable-hp2627win') HP2627a color graphics terminals.

'mftalk'
     ('--enable-mftalkwin') Generic window server (see
     'web2c/window/mftalk.c').

'next'
     ('--enable-next') NeXT window system.  This requires a separate
     program, called 'DrawingServant', available separately.  See the
     'web2c/window/next.c'.

'regis'
     ('--enable-regiswin') Regis terminals.

'sun'
     ('--enable-suntoolswin') The old Suntools (not any flavor of X)
     window system.  (You can get the even older SunWindows 'gfx' system
     by using 'sun-gfx.c'.)

'tek'
     ('--enable-tektronixwin') Tektronix terminals.

'uniterm'
     ('--enable-unitermwin') Uniterm, Simon Poole's emulator of a smart
     Tektronix 4014 terminal.  This may work with regular Tektronix
     terminals as well; it's faster than the driver
     '--enable-tektronixwin' selects.

'xterm'
     '--with-x' The X window system (version 11).

     There are two variants of the X11 support, one that works with the
     Xt toolkit, and another that works directly with Xlib.  The Xt
     support is more efficient and has more functionality, so it is the
     default.  If you must use the Xlib support, use 'configure --with-x
     --with-kf-x-toolkit=no'.

     Specify '--disable-mf-nowin' in order not to build a separate
     non-windows-capable Metafont executable 'mf-nowin' (or
     'mf-nowin.exe').

     You cannot specify any of the usual X options (e.g., '-geometry')
     on the Metafont command line, but you can specify X resources in
     your '~/.Xdefaults' or '~/.Xresources' file.  The class name is
     'Metafont'.  If you're using the Xt support, all the usual X
     toolkit resources are supported.  If you're using the Xlib support,
     only the 'geometry' resource is supported.

     You specify the X display to which Metafont connects in the
     'DISPLAY' environment variable, as usual.

   Writing support for a new device is straightforward.  Aside from
defining the basic drawing routines that Metafont uses (see 'mf.web'),
you only have to add another entry to the tables on the last page of
'web2c/lib/texmfmp.c'.  Or you can write an independent program and use
MFtalk (see 'web2c/window/mftalk.c').


File: web2c.info,  Node: gftodvi invocation,  Next: mft invocation,  Prev: Online Metafont graphics,  Up: Metafont

6.5 GFtoDVI: Character proofs of fonts
======================================

GFtoDVI makes "proof sheets" from a GF bitmap file as output by, for
example, Metafont (*note Metafont::).  This is an indispensable aid for
font designers or Metafont hackers.  Synopsis:

     gftodvi [OPTION]... GFNAME[gf]

   The font GFNAME is searched for in the usual places (*note
(kpathsea)Glyph lookup::).  To see all the relevant paths, set the
environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   The suffix 'gf' is supplied if not already present.  This suffix is
not an extension, no '.' precedes it; for instance, 'cmr10.600gf'.

   The output filename is the basename of GFNAME extended with '.dvi',
e.g., 'gftodvi /wherever/foo.600gf' creates './foo.dvi'.

   The characters from GFNAME appear one per page in the DVI output,
with labels, titles, and annotations, as specified in Appendix H
(Hardcopy Proofs) of 'The Metafontbook'.

   GFtoDVI uses several fonts besides GFNAME itself:

   * "gray font" (default 'gray'): for the pixels that actually make up
     the character.  Simply using black is not right, since then labels,
     key points, and other information could not be shown.

   * "title font" (default 'cmr8'): for the header information at the
     top of each output page.

   * "label font" (default 'cmtt10'): for the labels on key points of
     the figure.

   * "slant font" (no default): for diagonal lines, which are otherwise
     simulated using horizontal and vertical rules.

   To change the default fonts, you must use 'special' commands in your
Metafont source file, typically via commands like 'slantfont slantlj4'.
There is no default slant font since no one printer is suitable as a
default.  You can make your own by copying one of the existing files,
such as '.../fonts/source/public/misc/slantlj4.mf' and then running 'mf'
on it.

   For testing purposes, you may it useful to run 'mf-nowin rtest' (hit
RETURN when it stops) to get a 'gf' file of a thorn glyph.  Or use 'mf'
instead of 'mf-nowin' to have the glyph(s) displayed on the screen.
After that, 'gftodvi rtest.2602gf' should produce 'rtest.dvi', which you
process as usual.

   The program accepts the following option, as well as the standard
'-verbose', '-help', and '-version' (*note Common options::):

'-overflow-label-offset=POINTS'
     Typeset the so-called overflow labels, if any, POINTS TeX points
     from the right edge of the character bounding box.  The default is
     a little over two inches (ten million scaled points, to be
     precise).  Overflow equations are used to locate coordinates when
     their actual position is too crowded with other information.


File: web2c.info,  Node: mft invocation,  Prev: gftodvi invocation,  Up: Metafont

6.6 MFT: Prettyprinting Metafont source
=======================================

MFT translates a Metafont program into a TeX document suitable for
typesetting, with the aid of TeX macros defined in the file
'mftmac.tex'.  Synopsis:

     mft [OPTION]... MFNAME[.mf]

   MFT searches the usual places for MFNAME (*note (kpathsea)Supported
file formats::).  To see all the relevant paths, set the environment
variable 'KPATHSEA_DEBUG' to '-1' before running the program.  The
output goes to the basename of MFNAME extended with '.tex', e.g., 'mft
/wherever/foo.mf' creates './foo.tex'.

   Line breaks in the input are carried over into the output; moreover,
blank spaces at the beginning of a line are converted to quads of
indentation in the output.  Thus, you have full control over the
indentation and line breaks.  Each line of input is translated
independently of the others.

   Further control is allowed via Metafont comments:
   * Metafont comments following a single '%' should be valid TeX input.
     But Metafont material can be included within vertical bars in a
     comment; this will be translated by MFT as if it were regular
     Metafont code.  For example, a comment like '% |x2r| is the tip of
     the bowl' will be translated into the TeX '% $x_{2r}$ is the ...',
     i.e., the 'x2r' is treated as an identifier.

   * '%%' indicates that the remainder of an input line should be copied
     verbatim to the output.  This is typically used to introduce
     additional TeX material at the beginning or an MFT job, e.g.  code
     to modify the standard layout or the formatting macros defined in
     'mftmac.tex', or to add a line saying '%%\bye' at the end of the
     job.  (MFT doesn't add this automatically in order to allow
     processing several files produces by MFT in the same TeX job.)

   * '%%% TOKEN1 OTHER-TOKENS' introduces a change in MFT's formatting
     rules; all the OTHER-TOKENS will henceforth be translated according
     to the current conventions for TOKEN1.  The tokens must be symbolic
     (i.e., not numeric or string tokens).  For example, the input line
          %%% addto fill draw filldraw
     says to format the 'fill', 'draw', and 'filldraw' operations of
     plain Metafont just like the primitive token 'addto', i.e., in
     boldface type.  Without such reformatting commands, MFT would treat
     'fill' like an ordinary tag or variable name.  In fact, you need a
     '%%%' command even to get parentheses to act like delimiters.

   * '%%%%' introduces an MFT comment, i.e., MFT ignores the remainder
     of such a line.

   * Five or more '%' signs should not be used.

   (The above description was edited from 'mft.web', written by
D.E. Knuth.)

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-change=CHFILE[.ch]'
     Apply the change file CHFILE as with Tangle and Weave (*note
     WEB::).

'-style=MFTFILE[.mft]'
     Read MFTFILE before anything else; a MFT style file typically
     contains only MFT directives as described above.  The default style
     file is named 'plain.mft', which defines this properly for programs
     using plain Metafont.  The MFT files is searched along the
     'MFTINPUTS' path; see *note (kpathsea)Supported file formats::.

     Other examples of MFT style files are 'cmbase.mft', which defines
     formatting rules for the macros defined in 'cm.base', and 'e.mft',
     which was used in the production of Knuth's Volume E, 'Computer
     Modern Typefaces'.

     Using an appropriate MFT style file, it is also possible to
     configure MFT for typesetting MetaPost sources.  However, MFT does
     not search the usual places for MetaPost input files.

   If you use eight-bit characters in the input file, they are passed on
verbatim to the TeX output file; it is up to you to configure TeX to
print these properly.


File: web2c.info,  Node: MetaPost,  Next: BibTeX,  Prev: Metafont,  Up: Top

7 MetaPost: Generating PostScript
*********************************

MetaPost is a picture-drawing language similar to Metafont (*note
Metafont::), but instead of outputting bitmaps in a "font", it outputs
PostScript commands.  It's primarily intended for creating technical
illustrations, but can also be used to create PostScript or OpenType
fonts (<https://ctan.org/pkg/metatype1>).

   MetaPost also provides for arbitrary integration of text and graphics
in a natural way, using any typesetter (TeX and Troff are both
supported) and a number of other subsidiary programs, described below.

* Menu:

* mpost invocation::            Invoking MetaPost.
* Initial MetaPost::            Making mems.
* dvitomp invocation::          DVI-to-MPX translation.


File: web2c.info,  Node: mpost invocation,  Next: Initial MetaPost,  Up: MetaPost

7.1 'mpost' invocation
======================

MetaPost (installed as 'mpost') reads a series of pictures specified in
the MetaPost programming language, and outputs corresponding PostScript
code.  This section merely describes the options available in the Web2c
implementation.  For a complete description of the MetaPost language,
see AT&T technical report CSTR-162, generally available in
'TEXMF/doc/metapost/', where TEXMF is the root of TeX directory
structure.  See also:
   * <http://cm.bell-labs.com/who/hobby/MetaPost.html> (the MetaPost
     author's home page);
   * <http://tug.org/metapost> (papers, packages, and related
     information).

   Also, a standard MetaPost package for drawing graphs is documented in
AT&T technical report CSTR-164, available as the file 'mpgraph.ps',
generally stored alongside 'mpman.ps'.

   MetaPost processes its command line and determines its memory dump
(mem) file in a way exactly analogous to Metafont and TeX (*note 'tex'
invocation: tex invocation, and *note Memory dumps::).  Synopses:

     mpost [OPTION]... [MPNAME[.mp]] [MP-COMMANDS]
     mpost [OPTION]... \FIRST-LINE
     mpost [OPTION]... &MEM ARGS

   MetaPost searches the usual places for the main input file MPNAME
(*note (kpathsea)Supported file formats::), extending MPNAME with '.mp'
if necessary.  To see all the relevant paths, set the environment
variable 'KPATHSEA_DEBUG' to '-1' before running the program.

   MetaPost writes its PostScript output to a series of files
'BASEMPNAME.NNN' (or perhaps 'BASEMPNAME.ps', very occasionally
'BASEMPNAME.tfm'), where NNN are the figure numbers specified in the
input, typically to the 'beginfig' macro, and BASEMPNAME is the basename
of MPNAME, or 'mpout' if no input file was specified.  MetaPost uses the
'.ps' extension when the figure number is out of range, e.g., if you say
'beginfig(-1)'.

   You can use the output files as figures in a TeX document just as
with any other PostScript figures.  For example, with this TeX command:
     \special{psfile="FILENAME"}
or by using 'epsf.tex' (*note (dvips)EPSF macros::).

   The MetaPost construct
     btex ... TEX-INPUT ... etex
generates a MetaPost picture expression corresponding to TEX-INPUT.

   The construct
     verbatimtex ... TEX-INPUT ... etex
simply passes the TEX-INPUT through to TeX.  For example, if you are
using LaTeX, your MetaPost input file must start with a 'verbatimtex'
block that gives the necessary '\documentclass' (or '\documentstyle')
'\begin{document}' command.  You will also need to set the enviroment
variable 'TEX' to 'latex'.

   TEX-INPUT need not be specifically TeX input; it could also be Troff.
In that case, you will need the '-m pictures' Troff macro package
(unfortunately absent from many Troff implementations), or an equivalent
such as the '-m pspic' macros from GNU groff described in grops(1).

   Naturally, you must use fonts that are supported by the typesetter;
specifically, you'll probably want to use standard PostScript fonts with
Troff.  And only the TeX system understands Computer Modern or other
Metafont fonts; you can also use PostScript fonts with TeX, of course.

   MetaPost-generated PostScript figures which do use Computer Modern
fonts for labels cannot be directly previewed or printed.  Instead, you
must include them in a TeX document and run the resulting DVI file
through Dvips to arrange for the downloading of the required fonts
(*note (dvips)Fonts in figures::).  To help with this, the MetaPost
distribution provides a small TeX file 'mproof.tex' which is typically
called as:
     tex mproof MP-OUTPUT-FILES... ; dvips mproof -o
The resulting file 'mproof.ps' can then be printed or previewed.

   To generate EPSF files, set the internal MetaPost variable
'prologues' positive.  To make the output files self-contained, use only
standard PostScript fonts.  MetaPost reads the same 'psfonts.map' file
as Dvips, to determine PostScript fonts that need to be downloaded
(*note (dvips)psfonts.map::).

   It is posible for pdfTeX to read MetaPost output directly; this is in
contrast to general EPSF files, which have to be converted for use with
PDF output.  The easiest way is to name the MetaPost output files with
the '.mps' extension.  Then the LaTeX '\includegraphics' command, for
example, will be able to read them, even when outputting PDF.

   MetaPost can write output files, via the 'write' primitive; this
opens a security hole.  *Note tex invocation::.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-[no]-file-line-error'
'-fmt=FMTNAME'
'-halt-on-error'
'-ini'
'-interaction=STRING'
'-jobname=STRING'
'-kpathsea-debug=NUMBER'
'-[no]parse-first-line'
'-output-directory'
'-progname=STRING'
'-recorder'
'-translate-file=TCXFILE'
'-8bit'
     These options are common to TeX, Metafont, and MetaPost.  *Note
     Common options::.

'-T'
'-troff'
     Set the 'prologues' internal variable to '1'.

'-tex=TEXPROGRAM'
     When this option is given, the program TEXPROGRAM is used to
     typeset the labels.


File: web2c.info,  Node: Initial MetaPost,  Next: dvitomp invocation,  Prev: mpost invocation,  Up: MetaPost

7.2 Initial MetaPost
====================

As of MetaPost 1.504 (TeX Live 2011), MetaPost no longer dumps '.mem'
files (*note Memory dumps::) and does not distinguish virgin and initial
forms (*note Initial and virgin::).  Instead, the "initial" file name is
read in its source form--that is, 'mpost.mp' when the program is invoked
as 'mpost'.

   For a list of options and other information, see *note mpost
invocation::.

   MetaPost provides a format with all the features of plain Metafont,
called 'mfplain'.  You can use that in the same way; just run 'mfplain'
instead of 'mpost'.  This lets you directly process Metafont source
files with MetaPost, producing character proofs (one file for each
character) similar to those produced with Metafont in proof mode and
GFtoDVI (*note gftodvi invocation::).


File: web2c.info,  Node: dvitomp invocation,  Prev: Initial MetaPost,  Up: MetaPost

7.3 DVItoMP: DVI to MPX conversion
==================================

DVItoMP converts DVI files into low-level MetaPost commands in a
so-called MPX file.  Synopsis:

     dvitomp DVIFILE[.dvi] [MPXFILE[.mpx]]

If MPXFILE is not specified, the output goes to the basename of DVIFILE
extended with '.mpx', e.g., 'dvitomp /wherever/foo.dvi' creates
'./foo.mpx'.

   DVItoMP supports Dvips-style color specials, such as 'color push
NAME' and 'color pop', outputting them as 'withcolor' MetaPost commands.

   The only options are '-help' and '-version' (*note Common options::).


File: web2c.info,  Node: BibTeX,  Next: WEB,  Prev: MetaPost,  Up: Top

8 BibTeX: Bibliographies
************************

BibTeX automates much of the job of typesetting bibliographies, and
makes bibliography entries reusable in many different contexts.

* Menu:

* bibtex invocation::
* Basic BibTeX style files::    The standard and semi-standard styles.


File: web2c.info,  Node: bibtex invocation,  Next: Basic BibTeX style files,  Up: BibTeX

8.1 BibTeX invocation
=====================

BibTeX creates a printable bibliography ('.bbl') file from references in
a '.aux' file, generally written by TeX or LaTeX.  The '.bbl' file is
then incorporated on a subsequent run.  The basic bibliographic
information comes from '.bib' files, and a BibTeX style ('.bst') file
controls the precise contents of the '.bbl' file.  Synopsis:

     bibtex [OPTION]... AUXFILE[.aux]

The output goes to the basename of AUXFILE extended with '.bbl'; for
example, 'bibtex /wherever/foo.aux' creates './foo.bbl'.  BibTeX also
writes a log file to the basename of AUXFILE extended with '.blg'.

   The names of the '.bib' and '.bst' files are specified in the '.aux'
file as well, via the '\bibliography' and '\bibliographystyle' (La)TeX
macros.  BibTeX searches for '.bib' files using the 'BIBINPUTS' and
'TEXBIB' paths, and for '.bst' files using 'BSTINPUTS' (*note
(kpathsea)Supported file formats::).  It does no path searching for
'.aux' files.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-terse'
     Suppress the program banner and progress reports normally output.

'-min-crossrefs=N'
     If at least N (2 by default) bibliography entries refer to another
     entry E via their 'crossref' field, include E in the .bbl file,
     even if it was not explicitly referenced in the .aux file.  For
     example, E might be a conference proceedings as a whole, with the
     cross-referencing entries being individual articles published in
     the proceedings.

     If you want to avoid these automatic inclusions altogether, make N
     a sufficiently large number, and be sure to remove any previous
     .aux and .bbl files.  Otherwise the option may appear to have no
     effect, since BibTeX will have added the citation for E to the
     .aux, and nothing will remove it.

   See also:
'btxdoc.tex'
     Basic LaTeXable documentation for general BibTeX users.

'btxhak.tex'
     LaTeXable documentation for style designers.

'btxdoc.bib'
     BibTeX database file for the two above documents.

'xampl.bib'
     Example database file with all the standard entry types.

'<ftp://ftp.math.utah.edu/pub/tex/bib/>'
     A very large '.bib' and '.bst' collection, including references for
     all the standard TeX books and a complete bibliography for TUGboat.


File: web2c.info,  Node: Basic BibTeX style files,  Prev: bibtex invocation,  Up: BibTeX

8.2 Basic BibTeX style files
============================

Here are descriptions of the four standard and four semi-standard basic
BibTeX styles.  'CTAN:/biblio/bibtex' contains these and many more (for
CTAN info, *note (kpathsea)unixtex.ftp::).

'plain'
     Sorts entries alphabetically, with numeric labels.  Generally
     formatted according to van Leunen's 'A Handbook for Scholars'.  The
     other style files listed here are based on 'plain'.

'abbrv'
     First names, month names, and journal names are abbreviated.

'acm'
     Names are printed in small caps.

'alpha'
     Alphanumeric labels, e.g., 'Knu66'.

'apalike'
     No labels at all; instead, the year appears in parentheses after
     the author.  Use this in conjunction with 'apalike.tex' (plain TeX)
     or 'apalike.sty' (LaTeX), which also changes the citations in the
     text to be '(AUTHOR, YEAR)'.

'ieeetr'
     Numeric labels, entries in citation order, IEEE abbreviations,
     article titles in quotes.

'siam'
     Numeric labels, alphabetic order, 'Math. Reviews' abbreviations,
     names in small caps.

'unsrt'
     Lists entries in citation order, i.e., unsorted.

'btxbst.doc'
     The template file and documentation for the standard styles.


File: web2c.info,  Node: WEB,  Next: DVI utilities,  Prev: BibTeX,  Up: Top

9 WEB: Literate programming
***************************

"WEB" languages allow you to write a single source file that can produce
both a compilable program and a well-formatted document describing the
program in as much detail as you wish to prepare.  Writing in this kind
of dual-purpose language is called "literate programming".  (The Usenet
newsgroup 'comp.programming.literate' is devoted to this subject.)

   WEB-like languages have been implemented with many pairs of base
languages: Cweb provides C and Troff (*note References::); CWEB provides
C and TeX ('CTAN:/web/c_cpp/cweb'); Spiderweb provides C, C++, Awk, Ada,
many others, and TeX ('CTAN:/web/spiderweb'); and, of course, the
original WEB provides Pascal and TeX, the implementation languages for
the original TeX, Metafont, MetaPost, and related programs to come from
the TeX project at Stanford.

   The original WEB language is documented in the file 'webman.tex',
which is included in the <ftp://ftp.tug.org/tex/lib.tar.gz> archive (and
available in many other places, of course).

* Menu:

* tangle invocation::
* weave invocation::
* pooltype invocation::


File: web2c.info,  Node: tangle invocation,  Next: weave invocation,  Up: WEB

9.1 Tangle: Translate WEB to Pascal
===================================

Tangle creates a compilable Pascal program from a WEB source file (*note
WEB::).  Synopsis:

     tangle [OPTION]... WEBFILE[.web] [CHANGEFILE[.ch]]

The Pascal output is written to the basename of WEBFILE extended with
'.p'; for example, 'tangle /wherever/foo.web' creates './foo.p'.  Tangle
applies CHANGEFILE to WEBFILE before writing the output; by default,
there is no change file.

   If the program makes use of the WEB string facility, Tangle writes
the string pool to the basename of WEBFILE extended with '.pool'.

   The Pascal output is packed into lines of 72 characters or less, with
the only concession to readability being the termination of lines at
semicolons when this can be done conveniently.

   The program accepts the following options, as well as the standard
'--help' and '--version' (*note Common options::):

'-length=NUMBER'
     The number of characters that are considered significant in an
     identifier.  Whether underline characters are counted depends on
     the '-underline' option.  The default value is 32, the original
     tangle used 7, but this proved too restrictive for use by Web2c.

'-lowercase'
'-mixedcase'
'-uppercase'
     These options specify the case of identifiers in the output of
     tangle.  If '-uppercase' ('-lowercase') is specified, tangle will
     convert all identfiers to uppercase (lowercase).  The default is
     '-mixedcase', which specifies that the case will not be changed.

'-underline'
     When this option is given, tangle does not strip underline
     characters from identifiers.

'-loose'
'-strict'
     These options specify how strict tangle must be when checking
     identifiers for equality.  The default is '-loose', which means
     that tangle will follow the rules set by the case-smashing and
     underline options above.  If '-strict' is set, then identifiers
     will always be stripped of underlines and converted to uppercase
     before checking whether they collide.


File: web2c.info,  Node: weave invocation,  Next: pooltype invocation,  Prev: tangle invocation,  Up: WEB

9.2 Weave: Translate WEB to TeX
===============================

Weave creates a TeX document from a WEB source file (*note WEB::),
assuming various macros defined in 'webmac.tex'.  It takes care of
typographic details such as page layout, indentation, and italicizing
identifiers.  It also automatically gathers and outputs extensive
cross-reference information.  Synopsis:

     weave [OPTION]... WEBFILE[.web] [CHANGEFILE[.ch]]

The output is to the basename of WEBFILE extended with '.tex'; for
example, 'weave /wherever/foo.web' creates './foo.tex'.  Weave applies
CHANGEFILE to WEBFILE before writing the output; by default, there is no
change file.

   The program accepts the following option, as well as the standard
'-verbose', '-help' and '-version' (*note Common options::):
'-x'
     Omit the cross-reference information: the index, the list of WEB
     module names, and the table of contents (an empty 'CONTENTS.tex'
     file will still be written when the Weave output file is processed
     by TeX using the default 'webmac.tex', though).

   Conventionally, WEB programmers should define the TeX '\title' macro
at the beginning of the source file.  Also, to get output of only
changed modules, one can say '\let\maybe=\iffalse' (usually as the first
change in the change file).


File: web2c.info,  Node: pooltype invocation,  Prev: weave invocation,  Up: WEB

9.3 Pooltype: Display WEB pool files
====================================

Pooltype shows the so-called "string number" of each string in a WEB
pool file (*note WEB::), as output by Tangle (*note tangle
invocation::), including the first 256 strings corresponding to the
possible input characters.  Pooltype primarily serves as an example of
WEB conventions to implementors of the TeX system.  Synopsis:

     pooltype [OPTION]... POOLFILE[.pool]

No path searching is done for POOLFILE.  Output is to standard output.

   The only options are '--help' and '--version' (*note Common
options::).

   As an example of the output, here is the (edited) output for
'tex.pool':
     0: "^^@"
     1: "^^A"
     ...
     255: "^^ff"
     256: "pool size"
     ...
     1314: "Using character substitution: "
     (23617 characters in all.)

   In Metafont and MetaPost, the first 256 characters are actually
represented as single bytes (i.e., themselves), not in the '^^'
notation.  Consider Pooltype as showing the results after conversion for
output.


File: web2c.info,  Node: DVI utilities,  Next: Font utilities,  Prev: WEB,  Up: Top

10 DVI utilities
****************

TeX outputs a file in "DVI" (DeVice Independent) format as a compact
representation of the original document.  DVI files can be translated to
meet the requirements of a real physical device, such as PostScript
printers (*note Introduction: (dvips)Top.), PCL printers (see dvilj(1)),
and X displays (see xdvi(1)).  In fact, DVI translators are available
for virtually all common devices: see 'CTAN:/dviware' (for CTAN info,
*note (kpathsea)unixtex.ftp::).

   For the precise definition of the DVI file format, see (for example)
the source file 'web2c/dvitype.web'.

   The DVI-processing programs in the Web2c distribution are not device
drivers; they perform generic utility functions.

* Menu:

* dvicopy invocation::          Expand virtual fonts.
* dvitype invocation::          DVI to human-readable text.


File: web2c.info,  Node: dvicopy invocation,  Next: dvitype invocation,  Up: DVI utilities

10.1 DVIcopy: Canonicalize virtual font references
==================================================

DVIcopy reads a DVI file, expands any references to virtual fonts (*note
(dvips)Virtual fonts::) to base fonts, and writes the resulting DVI
file.  Thus you can use virtual fonts even if your DVI processor does
not support them, by passing the documents through DVIcopy first.
Synopsis:

     dvicopy [OPTION]... [INDVI[.dvi] [OUTDVI[.dvi]]]

   DVIcopy reads standard input if INDVI is not specified, and writes
standard output if OUTDVI is not specified.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-magnification=INTEGER'
     Override existing magnification in INDVI with INTEGER; 1000
     specifies no magnification.  This is equivalent to setting TeX's
     '\mag' parameter.

'-max-pages=N'
     Process N pages; default is one million.

'-page-start=PAGE-SPEC'
     Start at the first page matching PAGE-SPEC, which is one or more
     (signed) integers separated by periods, corresponding to TeX's
     '\count0...9' parameters at '\shipout' time; '*' matches anything.
     Examples: '3', '1.*.-4'.


File: web2c.info,  Node: dvitype invocation,  Prev: dvicopy invocation,  Up: DVI utilities

10.2 DVItype: Plain text transliteration of DVI files
=====================================================

DVItype translates a DeVice Independent (DVI) file (as output by TeX,
for example) to a plain text file that humans can read.  It also serves
as a DVI-validating program, i.e., if DVItype can read a file, it's
correct.  Synopsis:

     dvitype [OPTION]... DVIFILE[.dvi]

DVItype does not read any bitmap files, but it does read TFM files for
fonts referenced in DVIFILE.  The usual places are searched (*note
(kpathsea)Supported file formats::).  To see all the relevant paths, set
the environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   Output goes to standard output.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-dpi=REAL'
     Do pixel movement calculations at REAL pixels per inch; default
     300.0.

'-magnification=INTEGER'
     Override existing magnification in INDVI with INTEGER; 1000
     specifies no magnification.  This is equivalent to setting TeX's
     '\mag' parameter.

'-max-pages=N'
     Process N pages; default is one million.

'-output-level=N'
     Verbosity level of output, from 0 to 4 (default 4):
        * 0: Global document information only.
        * 1: Most DVI commands included, and typeset characters
          summarized.
        * 2: Character and movement commands explicitly included.
        * 3: DVI stack and current position calculations included.
        * 4: Same information as level 3, but DVItype does random
          positioning in the file, reading the DVI postamble first.

'-page-start=PAGE-SPEC'
     Start at the first page matching PAGE-SPEC, which is one or more
     (signed) integers separated by periods, corresponding to TeX's
     '\count0...9' parameters at '\shipout' time; '*' matches anything.
     Examples: '1', '5.*.-9'.

'-show-opcodes'
     Show numeric opcode values (in decimal) for DVI commands, in braces
     after the command name.  This can help in debugging DVI utilities.
     We use decimal because in the DVI format documentation (in
     'dvitype.web', among others) the opcodes are shown in decimal.

* Menu:

* dvitype output example::


File: web2c.info,  Node: dvitype output example,  Up: dvitype invocation

10.2.1 DVItype output example
-----------------------------

As an example of the output from DVItype (see section above), here is
its (abridged) translation of the 'story.dvi' resulting from running the
example in 'The TeXbook', with '-output-level=4' and '-show-opcodes' on.

     ...
     Options selected:
       Starting page = *
       Maximum number of pages = 1000000
       Output level = 4 (the works)
       Resolution = 300.00000000 pixels per inch
     numerator/denominator=25400000/473628672
     magnification=1000;       0.00006334 pixels per DVI unit
     ' TeX output 1992.05.17:0844'
     Postamble starts at byte 564.
     maxv=43725786, maxh=30785863, maxstackdepth=3, totalpages=1
     Font 33: cmsl10---loaded at size 655360 DVI units
     Font 23: cmbx10---loaded at size 655360 DVI units
     Font 0: cmr10---loaded at size 655360 DVI units

     42: beginning of page 1
     87: push {141}
     level 0:(h=0,v=0,w=0,x=0,y=0,z=0,hh=0,vv=0)
     88: down3 -917504 {159} v:=0-917504=-917504, vv:=-58
     92: pop {142}
     ...
     104: putrule {137} height 26214, width 30785863 (2x1950 pixels)
     113: down3 5185936 {159} v:=655360+5185936=5841296, vv:=370
     117: push {141}
     level 1:(h=0,v=5841296,w=0,x=0,y=0,z=0,hh=0,vv=370)
     118: right4 12265425 {146} h:=0+12265425=12265425, hh:=777
     [ ]
     123: fntdef1 23 {243}: cmbx10
     145: fntnum23 {194} current font is cmbx10
     146: setchar65 h:=12265425+569796=12835221, hh:=813
     147: w3 251220 {150} h:=12835221+251220=13086441, hh:=829
     151: setchar83 h:=13086441+418700=13505141, hh:=856
     ...
     164: setchar82 h:=17448202+565245=18013447, hh:=1142
     165: x0 -62805 {152} h:=18013447-62805=17950642, hh:=1138
     166: setchar89 h:=17950642+569796=18520438, hh:=1174
     [A SHORT STORY]
     167: pop {142}
     level 1:(h=0,v=5841296,w=0,x=0,y=0,z=0,hh=0,vv=370)
     ...
     550: pop {142}
     level 0:(h=0,v=42152922,w=0,x=0,y=0,z=0,hh=0,vv=2670)
     551: down3 1572864 {159} v:=42152922+1572864=43725786, vv:=2770
     555: push {141}
     level 0:(h=0,v=43725786,w=0,x=0,y=0,z=0,hh=0,vv=2770)
     556: right4 15229091 {146} h:=0+15229091=15229091, hh:=965
     561: setchar49 h:=15229091+327681=15556772, hh:=986
     [ 1]
     562: pop {142}
     level 0:(h=0,v=43725786,w=0,x=0,y=0,z=0,hh=0,vv=2770)
     563: eop {140}

   Explanation:

   * The DVItype options are recorded at the beginning, followed by
     global information about the document, including fonts used.

   * Each DVI command is preceded by its byte position in the file
     ('42:', '87:', ...), and (because of the '-show-opcodes') followed
     by its decimal opcode value in braces ('{141}', '{142}', ...).

   * The 'level' lines record information about the DVI stack; 'h' and
     'v' define the current position in DVI units, while 'hh' and 'vv'
     are the same in pixels.

   * Text sequences are summarized in brackets, as in '[A SHORT STORY]'
     and the '[ 1]'.


File: web2c.info,  Node: Font utilities,  Next: Legalisms,  Prev: DVI utilities,  Up: Top

11 Font utilities
*****************

The Web2c programs described here convert between various TeX-related
font formats; the first section below briefly describes the formats.
GFtoPK is the only one that is routinely used, as Metafont outputs GF
format, but it's most efficient for device drivers to use PK.

   The precise definitions of the PK, GF, TFM, PL, VF, and VPL formats
mentioned below are in the source files that read them; 'pktype.web',
'gftype.web', 'tftopl.web', etc.

* Menu:

* Font file formats::       Explanations of GF, PK, TFM, VF, ...
* gftopk invocation::       GF -> PK (compact)
* pktogf invocation::       PK -> GF (expand).
* pktype invocation::       PK -> human-readable text.
* gftype invocation::       GF -> human-readable text.
* tftopl invocation::       TFM -> PL (for editing TFM).
* pltotf invocation::       PL -> TFM (make editing results usable).
* vftovp invocation::       VF -> VPL (tftopl for virtual fonts).
* vptovf invocation::       VPL -> VF (pltotf for virtual fonts).
* Font utilities available elsewhere:: Type 1, BDF, editors, etc.


File: web2c.info,  Node: Font file formats,  Next: gftopk invocation,  Up: Font utilities

11.1 Font file formats
======================

(For another perspective on this, *note (dvips)Font concepts::).

   Font files come in several varieties, with suffixes like:
     .tfm  .*pk  .*gf  .*pxl (obsolete)  .pl  .mf  .vf  .vpl
Each represents a file format.

   A TFM (TeX font metric) file is a compact binary file that contains
information about each character in a font, about combinations of
characters within that font, and about the font as a whole.  The font
metric information contained in TFM files is device-independent units is
used by TeX to do typesetting.  Unlike the bitmap (raster) fonts
described below, TFM font files contain no information about the shapes
of characters.  They describe rectangular areas and combinations
thereof, but not what will eventually be printed in those areas.

   Since TeX does scaling calculations, one TFM file serves for all
magnifications of a given typeface.  On the other hand, the best printed
results are obtained when magnified (or reduced fonts) are not produced
geometrically (as done by PostScript, for example) but rather optically,
with each size a separate design (as done with Computer Modern and the
EC fonts, for example); then a separate TFM file is needed for each
size.

   At any rate, TeX produces a DVI (DeVice Independent) file from your
source document.  In order to print DVI files on real devices, you need
font files defining digitized character shapes and other data.  Then
previewers and printer-driver programs can translate your DVI files into
something usable by your monitor or printer.  Bitmap fonts come with
suffixes such as '.600pk' or '.600gf' or '.3000pxl', where the '600' is
the horizontal dots-per-inch resolution at which the font was produced,
and the 'pk' or 'gf' or 'pxl' indicates the font format.  Outline fonts
in PostScript Type 1 format have suffixes such as '.pfa' or '.pfb'.

   Fonts in pk (packed) format are in the tightly packed raster format
that is pretty much the standard today.  They take up less space than
fonts in the gf (generic font) format that Metafont generates, and far
less space than fonts in pxl format.  Fonts in pxl format take up gross
amounts of disk space and permit only 128 characters.  They are
obsolete.

   Font files with the '.pl' (property list) suffix are the plain text
(human-readable) analog of the binary '.tfm' files.  The TFtoPL and
PLtoTF programs convert between the two formats (*note tftopl
invocation:: and *note pltotf invocation::).

   Font files with the '.mf' suffix are in Metafont source format.
These are the files used by Metafont to generate rastered fonts for
specific typefaces at specific magnifications for the specific
resolution and type of mapping used by your device.

   The suffix '.vf' identifies "virtual font" files, for which '.vpl' is
the human-readable analog.  See *Note vftovp invocation::, and *note
vptovf invocation::.  For further discussion of virtual fonts, see
'CTAN:/doc/virtual-fonts.knuth', 'CTAN:/help/virtualfonts.txt', and
*note (dvips)Virtual fonts::.

   (This section is based on documentation in the original Unix TeX
distribution by Pierre MacKay and Elizabeth Tachikawa.)


File: web2c.info,  Node: gftopk invocation,  Next: pktogf invocation,  Prev: Font file formats,  Up: Font utilities

11.2 GFtoPK: Generic to packed font conversion
==============================================

GFtoPK converts a generic font (GF) file output by, for example,
Metafont (*note mf invocation::) to a packed font (PK) file.  PK files
are considerably smaller than the corresponding gf files, so they are
generally the bitmap font format of choice.  Some DVI-processing
programs, notably Dvips, only support PK files and not GF files.
Synopsis:

     gftopk [OPTION]... GFNAME.DPI[gf] [PKFILE]

The font GFNAME is searched for in the usual places (*note
(kpathsea)Glyph lookup::).  To see all the relevant paths, set the
environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   The suffix 'gf' is supplied if not already present.  This suffix is
not an extension; no '.' precedes it: for instance, 'cmr10.600gf'.

   If PKFILE is not specified, the output is written to the basename of
'GFNAME.DPIpk', e.g., 'gftopk /wherever/cmr10.600gf' creates
'./cmr10.600pk'.

   The only options are '--verbose', '--help', and '--version' (*note
Common options::).


File: web2c.info,  Node: pktogf invocation,  Next: pktype invocation,  Prev: gftopk invocation,  Up: Font utilities

11.3 PKtoGF: Packed to generic font conversion
==============================================

PKtoGF converts a packed font (PK) file to a generic font (GF) file.
Since PK format is much more compact than GF format, the most likely
reason to do this is to run GFtype (*note gftype invocation::) on the
result, so you can see the bitmap images.  Also, a few old utility
programs do not support PK format.  Synopsis:

     pktogf [OPTION]... PKNAME.DPI[pk] [GFFILE]

The font PKNAME is searched for in the usual places (*note
(kpathsea)Glyph lookup::).  To see all the relevant paths, set the
environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   The suffix 'pk' is supplied if not already present.  This suffix is
not an extension; no '.' precedes it: for instance, 'cmr10.600pk'.

   If GFFILE is not specified, the output is written to the basename of
'PKNAME.DPIgf', e.g., 'pktogf /wherever/cmr10.600pk' creates
'./cmr10.600gf'.

   The only options are '--verbose', '--help', and '--version' (*note
Common options::).


File: web2c.info,  Node: pktype invocation,  Next: gftype invocation,  Prev: pktogf invocation,  Up: Font utilities

11.4 PKtype: Plain text transliteration of packed fonts
=======================================================

PKtype translates a packed font (PK) bitmap file (as output by GFtoPK,
for example) to a plain text file that humans can read.  It also serves
as a PK-validating program, i.e., if PKtype can read a file, it's
correct.  Synopsis:

     pktype PKNAME.DPI[pk]

   The font PKNAME is searched for in the usual places (*note
(kpathsea)Glyph lookup::).  To see all the relevant paths, set the
environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   The suffix 'pk' is supplied if not already present.  This suffix is
not an extension; no '.' precedes it: for instance, 'cmr10.600pk'.

   The translation is written to standard output.

   The only options are '-help' and '-version' (*note Common options::).

   As an example of the output, here is the (abridged) translation of
the letter 'K' in 'cmr10', as rendered at 600dpi with the mode 'ljfour'
from <modes.mf> (available from 'ftp://ftp.tug.org/tex/modes.mf').

     955:  Flag byte = 184  Character = 75  Packet length = 174
       Dynamic packing variable = 11
       TFM width = 815562  dx = 4259840
       Height = 57  Width = 57  X-offset = -3  Y-offset = 56
       [2]23(16)17(8)9(25)11(13)7(27)7(16)7(28)4(18)7(28)2(20)7(27)...
       ...
       (14)9(24)12(5)[2]23(13)21

Explanation:

'955'
     The byte position in the file where this character starts.

'Flag byte'
'Dynamic packing variable'
     Related to the packing for this character; see the source code.

'Character'
     The character code, in decimal.

'Packet length'
     The total length of this character definition, in bytes.

'TFM width'
     The device-independent (TFM) width of this character.  It is 2^24
     times the ratio of the true width to the font's design size.

'dx'
     The device-dependent width, in "scaled pixels", i.e., units of
     horizontal pixels times 2^16.

'Height'
'Width'
     The bitmap height and width, in pixels.

'X-offset'
'Y-offset'
     Horizontal and vertical offset from the upper left pixel to the
     reference (origin) pixel for this character, in pixels (right and
     down are positive).  The "reference pixel" is the pixel that
     occupies the unit square in Metafont; the Metafont reference point
     is the lower left hand corner of this pixel.  Put another way, the
     x-offset is the negative of the left side bearing; the right side
     bearing is the horizontal escapement minus the bitmap width plus
     the x-offset.

'[2]23(16)...'
     Finally, run lengths of black pixels alternate with parenthesized
     run lengths of white pixels, and brackets indicate a repeated row.


File: web2c.info,  Node: gftype invocation,  Next: tftopl invocation,  Prev: pktype invocation,  Up: Font utilities

11.5 GFtype: Plain text transliteration of generic fonts
========================================================

GFtype translates a generic font (GF) bitmap file (as output by
Metafont, for example) to a plain text file that humans can read.  It
also serves as a GF-validating program, i.e., if GFtype can read a file,
it's correct.  Synopsis:

     gftype [OPTION]... GFNAME.DPI[gf]

   The font GFNAME is searched for in the usual places (*note
(kpathsea)Glyph lookup::).  To see all the relevant paths, set the
environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.

   The suffix 'gf' is supplied if not already present.  This suffix is
not an extension; no '.' precedes it: for instance, 'cmr10.600gf'.

   The translation is written to standard output.

   The program accepts the following options, as well as the standard
'-help' and '-version' (*note Common options::):
'-images'
     Show the characters' bitmaps using asterisks and spaces.

'-mnemonics'
     Translate all commands in the GF file.

   As an example of the output, here is the (abrdiged) translation of
the letter 'K' in 'cmr10', as rendered at 600dpi with the mode 'ljfour'
from 'modes.mf' (available from <ftp://ftp.tug.org/tex/modes.mf>), with
both '-mnemonics' and '-images' enabled.

   GFtype outputs the information about a character in two places: a
main definition and a one-line summary at the end.  We show both.  Here
is the main definition:

     2033: beginning of char 75: 3<=m<=60 0<=n<=56
     (initially n=56) paint (0)24(12)20
     2043: newrow 0 (n=55) paint 24(12)20
     2047: newrow 0 (n=54) paint 24(12)20
     2051: newrow 0 (n=53) paint 24(12)20
     2055: newrow 7 (n=52) paint 10(21)13
     2059: newrow 8 (n=51) paint 8(23)9
     ...
     2249: newrow 8 (n=5) paint 8(23)11
     2253: newrow 7 (n=4) paint 10(22)12
     2257: newrow 0 (n=3) paint 24(11)22
     2261: newrow 0 (n=2) paint 24(11)22
     2265: newrow 0 (n=1) paint 24(11)22
     2269: newrow 0 (n=0) paint 24(11)22
     2273: eoc
     .<--This pixel's lower left corner is at (3,57) in METAFONT coordinates
     ************************            ********************
     ************************            ********************
     ************************            ********************
     ************************            ********************
            **********                     *************
             ********                       *********
     ...
             ********                       ***********
            **********                      ************
     ************************           **********************
     ************************           **********************
     ************************           **********************
     ************************           **********************
     .<--This pixel's upper left corner is at (3,0) in METAFONT coordinates

Explanation:

'2033'
'2043'
'...'
     The byte position in the file where each GF command starts.

'beginning of char 75'
     The character code, in decimal.

'3<=m<=60 0<=n<=56'
     The character's bitmap lies between 3 and 60 (inclusive)
     horizontally, and between 0 and 56 (inclusive) vertically.  (m is a
     column position and n is a row position.)  Thus, 3 is the left side
     bearing.  The right side bearing is the horizontal escapement
     (given below) minus the maximum m.

'(initially n=56) paint (0)24(12)20'
     The first row of pixels: 0 white pixels, 24 black pixels, 12 white
     pixels, etc.

'newrow 0 (n=55) paint 24(12)20'
     The second row of pixels, with zero leading white pixels on the
     row.

'eoc'
     The end of the main character definition.

   Here is the GF postamble information that GFtype outputs at the end:

     Character 75: dx 4259840 (65), width 815562 (64.57289), loc 2033

   Explanation:

'dx'
     The device-dependent width, in "scaled pixels", i.e., units of
     horizontal pixels times 2^16.  The '(65)' is simply the same number
     rounded.  If the vertical escapement is nonzero, it would appear
     here as a 'dy' value.

'width'
     The device-independent (TFM) width of this character.  It is 2^24
     times the ratio of the true width to the font's design size.  The
     '64.57289' is the same number converted to pixels.

'loc'
     The byte position in the file where this character starts.


File: web2c.info,  Node: tftopl invocation,  Next: pltotf invocation,  Prev: gftype invocation,  Up: Font utilities

11.6 TFtoPL: TeX font metric to property list conversion
========================================================

TFtoPL translates a TeX font metric (TFM, *note (dvips)Metric files::)
file (as output by Metafont, for example) to "property list format" (a
list of parenthesized items describing the font) that humans can edit or
read.  This program is mostly used by people debugging TeX
implementations, writing font utilities, etc.  Synopsis:

     tftopl [OPTION]... TFMNAME[.tfm] [PLFILE[.pl]]

   The font TFMNAME (extended with '.tfm' if necessary) is searched for
in the usual places (*note (kpathsea)Supported file formats::).  To see
all the relevant paths, set the environment variable 'KPATHSEA_DEBUG' to
'-1' before running the program.

   If PLFILE (which is extended with '.pl' if necessary) is not
specified, the property list file is written to standard output.  The
property list file can be converted back to TFM format by the companion
program TFtoPL (see the next section).

   The program accepts the following option, as well as the standard
'-verbose', '-help' and '-version' (*note Common options::):
'-charcode-format=TYPE'
     Output character codes in the PL file according to TYPE: either
     'octal' or 'ascii'.  Default is 'ascii' for letters and digits,
     octal for all other characters.  Exception: if the font's coding
     scheme starts with 'TeX math sy' or 'TeX math ex', all character
     codes are output in octal.

     In 'ascii' format, character codes that correspond to graphic
     characters, except for left and right parentheses, are output as a
     'C' followed by the single character: 'C K', for example.  In octal
     format, character codes are output as the letter 'O' followed by
     octal digits, as in 'O 113' for 'K'.

     'octal' format is useful for symbol and other non-alphabetic fonts,
     where using ASCII characters for the character codes is merely
     confusing.

   As an example of the output, here is the (abridged) property list
translation of 'cmr10.tfm':

     (FAMILY CMR)
     (FACE O 352)
     (CODINGSCHEME TEX TEXT)
     (DESIGNSIZE R 10.0)
     (COMMENT DESIGNSIZE IS IN POINTS)
     (COMMENT OTHER SIZES ARE MULTIPLES OF DESIGNSIZE)
     (CHECKSUM O 11374260171)
     (FONTDIMEN
        (SLANT R 0.0)
        (SPACE R 0.333334)
        (STRETCH R 0.166667)
        (SHRINK R 0.111112)
        (XHEIGHT R 0.430555)
        (QUAD R 1.000003)
        (EXTRASPACE R 0.111112)
        )
     (LIGTABLE
        ...
        (LABEL C f)
        (LIG C i O 14)
        (LIG C f O 13)
        (LIG C l O 15)
        (KRN O 47 R 0.077779)
        (KRN O 77 R 0.077779)
        (KRN O 41 R 0.077779)
        (KRN O 51 R 0.077779)
        (KRN O 135 R 0.077779)
        (STOP)
        ...
        )
     ...
     (CHARACTER C f
        (CHARWD R 0.305557)
        (CHARHT R 0.694445)
        (CHARIC R 0.077779)
        (COMMENT
           (LIG C i O 14)
           (LIG C f O 13)
           (LIG C l O 15)
           (KRN O 47 R 0.077779)
           (KRN O 77 R 0.077779)
           ...
           )
        )
     ...

   As you can see, the general format is a list of parenthesized
"properties", nested where necessary.

   * The first few items ('FAMILY', 'FACE', and so on) are the so-called
     "headerbyte" information from Metafont, giving general information
     about the font.

   * The 'FONTDIMEN' property defines the TeX '\fontdimen' values.

   * The 'LIGTABLE' property defines the ligature and kerning table.
     'LIG' properties define ligatures: in the example above, an 'f' (in
     the 'LABEL') followed by an 'i' is a ligature, i.e., a typesetting
     program like TeX replaces those two consecutive characters by the
     character at position octal '014 in the current font--presumably
     the 'fi' ligature.  'KRN' properties define kerns: if an 'f' is
     followed by character octal '047 (an apostrophe), TeX inserts a
     small amount of space between them: 0.077779 times the design size
     the font was loaded at (about three-quarters of a printer's point
     by default in this case, or .001 inches).

   * The 'CHARACTER' property defines the dimensions of a character: its
     width, height, depth, and italic correction, also in design-size
     units, as explained in the previous item.  For our example 'f', the
     depth is zero, so that property is omitted.  TFtoPL also inserts
     any kerns and ligatures for this character as a comment.


File: web2c.info,  Node: pltotf invocation,  Next: vftovp invocation,  Prev: tftopl invocation,  Up: Font utilities

11.7 PLtoTF: Property list to TeX font metric conversion
========================================================

PLtoTF translates a property list file (as output by TFtoPL, for
example) to TeX font metric (TFM, *note (dvips)Metric files::) format.
It's much easier for both programs and humans to create the (plain text)
property list files and let PLtoTF take care of creating the binary TFM
equivalent than to output TFM files directly.  Synopsis:

     pltotf [OPTION]... PLFILE[.pl] [TFMFILE[.tfm]]

   If TFMFILE (extended with '.tfm' if necessary) is not specified, the
TFM file is written to the basename of 'PLFILE.tfm', e.g., 'pltotf
/wherever/cmr10.pl' creates './cmr10.tfm'.  (Since TFM files are binary,
writing to standard output by default is undesirable.)

   The only options are '-verbose', '-help', and '-version' (*note
Common options::).

   For an example of property list format, see the previous section.


File: web2c.info,  Node: vftovp invocation,  Next: vptovf invocation,  Prev: pltotf invocation,  Up: Font utilities

11.8 VFtoVP: Virtual font to virtual property lists
===================================================

VFtoVP translates a virtual font metric (VF, *note (dvips)Virtual
fonts::) file and its accompanying TeX font metric (TFM, *note
(dvips)Metric files::) file (as output by VPtoVF, for example) to
"virtual property list format" (a list of parenthesized items describing
the virtual font) that humans can edit or read.  This program is mostly
used by people debugging virtual font utilities.  Synopsis:

     vftovp [OPTION]... VFNAME[.vf] [TFMNAME[.tfm] [VPLFILE[.vpl]]]

   The fonts VFNAME and TFMNAME (extended with '.vf' and '.tfm' if
necessary) are searched for in the usual places (*note
(kpathsea)Supported file formats::).  To see all the relevant paths, set
the environment variable 'KPATHSEA_DEBUG' to '-1' before running the
program.  If TFMNAME is not specified, VFNAME (without a trailing '.vf')
is used.

   If VPLFILE (extended with '.vpl' if necessary) is not specified, the
property list file is written to standard output.  The property list
file can be converted back to VF and TFM format by the companion program
VFtoVP (see the next section).

   The program accepts the following option, as well as the standard
'-verbose', '-help' and '-version' (*note Common options::):
'-charcode-format=TYPE'
     Output character codes in the PL file according to TYPE: either
     'octal' or 'ascii'.  Default is 'ascii' for letters and digits,
     octal for all other characters.  Exception: if the font's coding
     scheme starts with 'TeX math sy' or 'TeX math ex', all character
     codes are output in octal.

     In 'ascii' format, character codes that correspond to graphic
     characters, except for left and right parentheses, are output as a
     'C' followed by the single character: 'C K', for example.  In octal
     format, character codes are output as the letter 'O' followed by
     octal digits, as in 'O 113' for 'K'.

     'octal' format is useful for symbol and other non-alphabetic fonts,
     where using ASCII characters for the character codes is merely
     confusing.


File: web2c.info,  Node: vptovf invocation,  Next: Font utilities available elsewhere,  Prev: vftovp invocation,  Up: Font utilities

11.9 VPtoVF: Virtual property lists to virtual font
===================================================

VPtoVF translates a virtual property list file (as output by VFtoVP, for
example) to virtual font (VF, *note (dvips)Virtual fonts::) and TeX font
metric (TFM, *note (dvips)Metric files::) files.  It's much easier for
both programs and humans to create the (plain text) property list files
and let VPtoVF take care of creating the binary VF and TFM equivalents
than to output them directly.  Synopsis:

     vptovf [OPTION]... VPLFILE[.vpl] [VFFILE[.vf] [TFMFILE[.tfm]]]

   If VFFILE (extended with '.vf' if necessary) is not specified, the VF
output is written to the basename of 'VPLFILE.vf'; similarly for
TFMFILE.  For example, 'vptovf /wherever/ptmr.vpl' creates './ptmr.vf'
and './ptmr.tfm'.

   The only options are '-verbose', '-help', and '-version' (*note
Common options::).


File: web2c.info,  Node: Font utilities available elsewhere,  Prev: vptovf invocation,  Up: Font utilities

11.10 Font utilities available elsewhere
========================================

The Web2c complement of font utilities merely implements a few basic
conversions.  Many other more sophisticated font utilities exist; most
are in 'CTAN:/fonts/utilities' (for CTAN info, *note
(kpathsea)unixtex.ftp::).  Here are some of the most commonly-requested
items:

   * AFM (Adobe font metric) to TFM conversion: *note (dvips)Invoking
     afm2tfm::, and 'CTAN:/fonts/utilities/afmtopl'.

   * BDF (the X bitmap format) conversion:
     <ftp://ftp.tug.org/tex/bdf.tar.gz>.

   * Creating fonts using MetaPost: MetaType1.
     <ftp://bop.eps.gda.pl/pub/metatype1>.  This is used to create the
     excellent Latin Modern font family ('CTAN:/fonts/lm'), which
     extends Computer Modern to a vast repertoire of scripts.

   * Editing of bitmap fonts: Xbfe from the GNU font utilities mentioned
     below; the X BDF-editing programs available from
     <ftp://ftp.x.org/R5contrib/xfed.tar.Z> and
     <ftp://ftp.x.org/R5contrib/xfedor.tar.Z>; and finally, if your
     fonts have only 128 characters, you can use the old 'gftopxl',
     'pxtoch', and 'chtopx' programs from <ftp://ftp.tug.org/tex/web>.

   * Editing of outline fonts: FontForge, <fontforge.sourceforge.net>.
     This is a very elaborate program with support for many outline
     formats (Type 1, OpenType, TrueType, ...), and many advanced font
     editing features.

   * PK bitmaps from PostScript outline fonts: gsftopk from the 'xdvi'
     distribution.  Alternatively, 'ps2pk', from
     'CTAN:/fonts/utilities/ps2pk'.

   * PostScript Type 1 font format conversion (i.e., between PFA and PFB
     formats): <http://www.lcdf.org/type>.

   * Scanned image conversion: the (aging) GNU font utilities convert
     type specimen images to Metafont, PostScript, etc.:
     <http://www.gnu.org/software/fontutils/>.

   * Tracing bitmaps to fitted outlines: Autotrace
     (<http://autotrace.sourceforge.net>), Potrace
     (<http://potrace.sourceforge.net>).  For Metafont fonts, either of
     the two programs 'mftrace' (<http://www.xs4all.nl/~hanwen/mftrace>)
     or 'textrace' (<http://textrace.sourceforge.net>) make the job
     easier.

   * Virtual font creation: 'CTAN:/fonts/utilities/fontinst'.


File: web2c.info,  Node: Legalisms,  Next: References,  Prev: Font utilities,  Up: Top

Appendix A Legalisms
********************

In general, each file has its own copyright notice stating the copying
permissions for that file.  Following is a summary.

   The Stanford TeX programs and Web2c system itself are in the public
domain (<https://tug.org/texlive/copying.html>).  The sources may be
copied verbatim, or used as the starting point of new software under
different names; however, per the wishes of the authors, they should be
modified only through a '.ch' file, but this is in the nature of a
development request rather than a legal requirement.

   MLTeX, pdfTeX, LuaTeX, XeTeX, and all the other derived engines have
used various license terms for their additions to the base code, often
the GPL (see <https://www.gnu.org/licenses/#GPL> or (for example) the
file 'web2c/pdftexdir/COPYINGv2'.  They also mostly make use of
additional libraries with their own (compatible) terms.  Please see each
program's sources.

   The Kpathsea library is covered by the GNU Lesser General Public
License (*note (kpathsea)Introduction::).  Therefore, the _binaries_
resulting from a standard Web2c compilation are also covered by the
LGPL; so if you (re)distribute the binaries, you must also (offer to)
distribute the complete source that went into those binaries.  See
<https://gnu.org/licenses/#LGPL> or the file
'kpathsea/COPYING.LESSERv2'.


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Appendix B References
*********************

  1. Kpathsea: *Note Introduction: (kpathsea)Top.

  2. Dvips and Afm2tfm: *Note Introduction: (dvips)Top.

  3. The TeX Users Group: <http://www.tug.org>.  For an introduction to
     the TeX system, see <http://tug.org/begin.html>.

  4. TUGboat: <http://tug.org/TUGboat>.

  5. TeX and computer typesetting in general:
     <ftp://ftp.math.utah.edu/pub/tex/bib/texbook1.bib>.

  6. For a bibliography of formal articles and technical reports on the
     TeX project, see the books 'TeX: The Program' or 'Metafont: The
     Program' cited below.

  7. [Bil87] Neenie Billawala.  Write-white printing engines and tuning
     fonts with Metafont.  'TUGboat', 8(1):29-32, April 1987.
     <https://tug.org/TUGboat/tb08-1/tb17billawala.pdf>.

  8. [Hob89] John D. Hobby.  A Metafont-like system with PS output.
     'TUGboat', 10(4):505-512, December 1989.
     <https://tug.org/metapost>.

  9. [Hob92] John D. Hobby.  A User's Manual for MetaPost.  Technical
     Report CSTR-162, AT&T Bell Laboratories, 1992.

  10. [Hob93] John D. Hobby.  Drawing Graphs with MetaPost.  Technical
     Report CSTR-164, AT&T Bell Laboratories, 1993.

  11. [HS91] Samuel P. Harbison and Guy L. Steele Jr.  'C--A Reference
     Manual'.  Prentice-Hall, Upper Saddle River, NJ 07458, USA, third
     edition, 1991.  An authoritative reference to the C programming
     language, and a good companion to Kernighan and Ritchie.

  12. [KL93] Donald E. Knuth and Silvio Levy.  'The CWEB System of
     Structured Documentation, Version 3.0'.  Addison-Wesley, Reading,
     MA, USA, 1993.  <https://ctan.org/pkg/cweb>.

  13. [Knu84] Donald E. Knuth.  A torture test for TeX.  Report No.
     STAN-CS-84-1027, Stanford University, Department of Computer
     Science, 1984.

  14. [Knu86a] Donald E. Knuth.  A Torture Test for METAFONT. Report No.
     STAN-CS-86-1095, Stanford University, Department of Computer
     Science, 1986.

  15. [Knu86b] Donald E. Knuth.  'The TeXbook', volume A of 'Computers
     and Typesetting'.  Addison-Wesley, Reading, MA, USA, 1986.

  16. [Knu86c] Donald E. Knuth.  'TeX: The Program', volume B of
     'Computers and Typesetting'.  Addison-Wesley, Reading, MA, USA,
     1986.

  17. [Knu86d] Donald E. Knuth.  'The METAFONTbook', volume C of
     'Computers and Typesetting'.  Addison-Wesley, Reading, MA, USA,
     1986.

  18. [Knu86e] Donald E. Knuth.  'METAFONT: The Program', volume D of
     'Computers and Typesetting'.  Addison-Wesley, Reading, MA, USA,
     1986.

  19. [Knu86f] Donald E. Knuth.  'Computer Modern Typefaces', volume E
     of 'Computers and Typesetting'.  Addison-Wesley, Reading, MA, USA,
     1986.

  20. [Knu89] Donald E. Knuth.  The errors of TeX.  'Software--Practice
     and Experience', 19(7):607-681, July 1989.  This is an updated
     version of Knuth:1988:ET.

  21. [Knu90] Donald Knuth.  Virtual Fonts: More Fun for Grand Wizards.
     'TUGboat', 11(1):13-23, April 1990.
     <https://tug.org/TUGboat/tb11-1/tb27knut.pdf>.

  22. [Knu92] Donald E. Knuth.  'Literate Programming'.  CSLI Lecture
     Notes Number 27.  Stanford University Center for the Study of
     Language and Information, Stanford, CA, USA, 1992.

  23. [Lam94] Leslie Lamport.  'LaTeX: A Document Preparation System:
     User's Guide and Reference Manual'.  Addison-Wesley, Reading, MA,
     USA, second edition, 1994.  Reprinted with corrections, 1996.

  24. [Lia83] Franklin Mark Liang.  Word hy-phen-a-tion by com-pu-ter.
     Technical Report STAN-CS-83-977, Stanford University, August 1983.
     <https://tug.org/docs/liang/liang-thesis.pdf>.

  25. [Mac91] Pierre A. MacKay.  Looking at the pixels: Quality control
     for 300 dpi laser printer fonts, especially Metafonts.  In Robert
     A. Morris and Jacques Andre, editors, 'Raster Imaging and Digital
     Typography II--Papers from the second RIDT meeting, held in Boston,
     Oct. 14-16, 1991', pages 205-215, New York, 1991.  Cambridge
     University Press.


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Index
*****