\section{Release history}
\label{sec:history}

\subsection{Past}

Discussion began in late 1993 when the Dutch \TeX{} Users Group was
starting work on its 4All\TeX{} \CD{} for \acro{MS-DOS} users, and it
was hoped at that time to issue a single, rational, \CD{} for all
systems. This was too ambitious a target for the time, but it did spawn
not only the very successful 4All\TeX{} \CD{}, but also the \acro{TUG}
Technical Council working group on a \emph{\TeX{} Directory Structure}
(\url{http://tug.org/tds}), which specified how to create consistent and
manageable collections of \TeX{} support files. A complete draft of the
\TDS{} was published in the December 1995 issue of \textsl{TUGboat}, and
it was clear from an early stage that one desirable product would be a
model structure on \CD{}. The distribution you now have is a very direct
result of the working group's deliberations. It was also clear that the
success of the 4All\TeX{} \CD{} showed that Unix users would benefit
from a similarly easy system, and this is the other main strand of
\TL.

We first undertook to make a new Unix-based \TDS{} \CD{} in the autumn
of 1995, and quickly identified Thomas Esser's \teTeX{} as the ideal
setup, as it already had multi-platform support and was built with
portability across file systems in mind. Thomas agreed to help, and work
began seriously at the start of 1996. The first edition was released in
May 1996. At the start of 1997, Karl Berry completed a major new release
of Web2c, which included nearly all the features which Thomas Esser had
added in \teTeX, and we decided to base the 2nd edition of the \CD{} on
the standard \Webc, with the addition of \teTeX's \texttt{texconfig}
script. The 3rd edition of the \CD{} was based on a major revision of
\Webc, 7.2, by Olaf Weber; at the same time, a new revision of \teTeX
was being made, and \TL{} included almost all of its features. The
4th edition followed the same pattern, using a new version of \teTeX,
and a new release of \Webc{} (7.3).  The system now included a complete
Windows setup.

For the 5th edition (March 2000) many parts of the \CD{} were revised
and checked, updating hundreds of packages. Package details were stored
in XML files. But the major change for \TeX\ Live 5 was that all
non-free software was removed. Everything in \TL{} is now intended
to be compatible with the Debian Free Software Guidelines
(\url{http://www.debian.org/intro/free}); we have done our best to check
the license conditions of all packages, but we would very much
appreciate hearing of any mistakes.

The 6th edition (July 2001) had much more material updated. The major
change was a new install concept: the user could select a more exact set
of needed collections. Language-related collections were completely
reorganized, so selecting any of them installs not only macros, fonts,
etc., but also prepares an appropriate \texttt{language.dat}.

The 7th edition of 2002 had the notable addition of \MacOSX{} support,
and the usual myriad of updates to all sorts of packages and
programs. An important goal was integration of the source back with
\teTeX, to correct the drift apart in versions~5 and~6.

\subsubsection{2003}

In 2003, with the continuing flood of updates and additions, we found
that \TL{} had grown so large it could no longer be contained on a
single \CD, so we split it into three different distributions (see
section~\ref{sec:multiple-dist}, \p.\pageref{sec:multiple-dist}).  In
addition:

\begin{itemize*}
\item At the request of the \LaTeX{} team, we changed the standard
      \cmdname{latex} and \cmdname{pdflatex} commands to now use \eTeX{} (see
      \p.\pageref{text:etex}).
\item The new Latin Modern fonts were included (and are recommended).
\item Support for Alpha \acro{OSF} was removed
      (\acro{HPUX} support was removed previously), since no one had (or
      volunteered) hardware available on which to compile new binaries.
\item Windows setup was substantially changed; for the first time
      an integrated environment based on XEmacs was introduced.
\item Important supplementary programs for Windows
      (Perl, Ghost\-script, Image\-Magick, Ispell) are now installed
      in the \TL{} installation directory.
\item Font map files used by \cmdname{dvips}, \cmdname{dvipdfm}
      and \cmdname{pdftex} are now generated by the new program
      \cmdname{updmap} and installed into \dirname{texmf/fonts/map}.
\item \TeX{}, \MF{}, and \MP{} now, by default, output most input
      characters (32 and above) as themselves in output (e.g.,
      \verb|\write|) files,
      log files, and the terminal, i.e., \emph{not} translated using the
      \verb|^^| notation.  In \TL{}~7, this translation was
      dependent on the system locale settings; now, locale settings do
      not influence the \TeX{} programs' behavior.  If for some reason
      you need the \verb|^^| output, rename the file
      \verb|texmf/web2c/cp8bit.tcx|.  (Future releases will have cleaner
      ways to control this.)
\item This documentation was substantially revised.
\item Finally, since the edition numbers had grown unwieldy,
      the version is now simply identified by the year: \TL{} 2003.
\end{itemize*}


\subsubsection{2004}

2004 saw many changes:

\begin{itemize}

\item If you have locally-installed fonts which use their own
\filename{.map} or (much less likely) \filename{.enc} support files, you
may need to move those support files.

\filename{.map} files are now searched for in subdirectories of
\dirname{fonts/map} only (in each \filename{texmf} tree), along the
\envname{TEXFONTMAPS} path.  Similarly, \filename{.enc} files are now
searched for in subdirectories of \dirname{fonts/enc} only, along the
\envname{ENCFONTS} path.  \cmdname{updmap} will attempt to warn about
problematic files.

For methods of handling this and other information, please see
\url{http://tug.org/texlive/mapenc.html}.

\item The \TK\ has been expanded with the addition of a \MIKTEX-based
installable \CD, for those who prefer that implementation to Web2C.
See section~\ref{sec:struct-tl} (\p.\pageref{sec:struct-tl}).

\item Within \TL, the single large \dirname{texmf} tree of previous
releases has been replaced by three: \dirname{texmf},
\dirname{texmf-dist}, and \dirname{texmf-doc}.  See
section~\ref{sec:tld} (\p.\pageref{sec:tld}), and the \filename{README}
files for each.

\item All \TeX-related input files are now collected in
the \dirname{tex} subdirectory of \dirname{texmf*} trees, rather than
having separate sibling directories \dirname{tex}, \dirname{etex},
\dirname{pdftex}, \dirname{pdfetex}, etc.  See
\CDref{texmf-doc/doc/english/tds/tds.html\#Extensions}
{\texttt{texmf-doc/doc/english/tds/tds.html\#Extensions}}.

\item Helper scripts (not meant to be invoked by users) are now located
in a new \dirname{scripts} directory of \dirname{texmf*} trees, and
searched for via \verb|kpsewhich -format=texmfscripts|.  So if you have
programs which call such scripts, they'll need to be adjusted.  See
\CDref{texmf-doc/doc/english/tds/tds.html\#Scripts}
{\texttt{texmf-doc/doc/english/tds/tds.html\#Scripts}}.

\item Almost all formats leave most characters printable as
themselves via the ``translation file'' \filename{cp227.tcx}, instead of
translating them with the \verb|^^| notation.  Specifically, characters
at positions 32--256, plus tab, vertical tab, and form feed are
considered printable and not translated.  The exceptions are plain \TeX\
(only 32--126 printable), \ConTeXt\ (0--255 printable), and the
\OMEGA-related formats.  This default behavior is almost the same as in
\TL\,2003, but it's implemented more cleanly, with more possibilities
for customization.  See \CDref{texmf/doc/web2c/web2c.html\#TCX-files}
{\texttt{texmf/doc/web2c/web2c.html\#TCX-files}}.
(By the way, with Unicode input, \TeX\ may output partial character
sequences when showing error contexts, since it is byte-oriented.)

\item \textsf{pdfetex} is now the default engine for all formats
except (plain) \textsf{tex} itself.  (Of course it generates \acro{DVI}
when run as \textsf{latex}, etc.)  This means, among other things, that
the microtypographic features of \textsf{pdftex} are available in
\LaTeX, \ConTeXt, etc., as well as the \eTeX\ features
(\OnCD{texmf-dist/doc/etex/base/}).

It also means it's \emph{more important than ever} to use the
\pkgname{ifpdf} package (works with both plain and \LaTeX) or equivalent
code, because simply testing whether \cs{pdfoutput} or some other
primitive is defined is not a reliable way to determine if \acro{PDF}
output is being generated.  We made this backward compatible as best we
could this year, but next year, \cs{pdfoutput} may be defined even when
\acro{DVI} is being written.

\item pdf\TeX\ (\url{http://pdftex.org}) has many new features:

  \begin{itemize*}

  \item \cs{pdfmapfile} and \cs{pdfmapline} provide font map support
  from within a document.

  \item Microtypographic font expansion can be used more easily.\\
  \url{http://www.ntg.nl/pipermail/ntg-pdftex/2004-May/000504.html}

  \item All parameters previously set through the special configuration
  file \filename{pdftex.cfg} must now be set through primitives,
  typically in \filename{pdftexconfig.tex}; \filename{pdftex.cfg} is no
  longer supported.  Any extant \filename{.fmt} files must be redumped
  when \filename{pdftexconfig.tex} is changed.

  \item See the pdf\TeX\ manual for more: \OnCD{texmf/doc/pdftex/manual}.

  \end{itemize*}

\item The \cs{input} primitive in \cmdname{tex} (and \cmdname{mf} and
\cmdname{mpost}) now accepts double quotes containing spaces and other
special characters.  Typical examples:
\begin{verbatim}
\input "filename with spaces"   % plain
\input{"filename with spaces"}  % latex
\end{verbatim}
See the Web2C manual for more: \OnCD{texmf/doc/web2c}.

\item enc\TeX\ support is now included within Web2C and consequently all
\TeX\ programs, via the \optname{-enc} option\Dash \emph{only when
formats are built}.  enc\TeX\ supports general re-encoding of input and
output, enabling full support of Unicode (in \acro{UTF}-8).  See
\OnCD{texmf-dist/doc/generic/enctex/} and
\url{http://www.olsak.net/enctex.html}.

\item Aleph, a new engine combining \eTeX\ and \OMEGA, is available.
A little information is available in \OnCD{texmf-dist/doc/aleph/base}
and \url{http://www.tex.ac.uk/cgi-bin/texfaq2html?label=aleph}.  The
\LaTeX-based format for Aleph is named \textsf{lamed}.

\item The latest \LaTeX\ release has a new version of the
\acro{LPPL}\Dash now officially a Debian-approved license.  Assorted
other updates, see the \filename{ltnews} files in
\OnCD{texmf-dist/doc/latex/base}.

\item \cmdname{dvipng}, a new program for converting \acro{DVI} to
\acro{PNG} image files, is included.  See \OnCD{texmf/doc/man/man1/dvipng.1}.

\item We reduced the \pkgname{cbgreek} package to a ``medium'' sized set
of fonts, with the assent and advice of the author (Claudio Beccari).
The excised fonts are the invisible, outline, and transparency ones,
which are relatively rarely used, and we needed the space.  The full set
is of course available from \acro{CTAN}
(\url{http://www.ctan.org/tex-archive/fonts/greek/cb}).

\item \cmdname{oxdvi} has been removed; just use \cmdname{xdvi}.

\item The \cmdname{ini} and \cmdname{vir} commands (links) for
\cmdname{tex}, \cmdname{mf}, and \cmdname{mpost} are no longer created,
such as \cmdname{initex}.  The \cmdname{ini} functionality has been
available through the command-line option \optname{-ini} for years now.

\item \textsf{i386-openbsd} platform support was removed.  Since the
\pkgname{tetex} package in the \acro{BSD} Ports system is available, and
\acro{GNU/}Linux and Free\acro{BSD} binaries were available, it seemed
volunteer time could be better spent elsewhere.

\item On \textsf{sparc-solaris} (at least), you may have to set the
\envname{LD\_LIBRARY\_PATH} environment variable to run the
\pkgname{t1utils} programs.  This is because they are compiled with C++,
and there is no standard location for the runtime libraries.  (This is
not new in 2004, but wasn't previously documented.)  Similarly, on
\textsf{mips-irix}, the \acro{MIPS}pro 7.4 runtimes are required.

\end{itemize}

\subsubsection{2005}

2005 saw the usual huge number of updates to packages and programs.
The infrastructure stayed relatively stable from 2004, but inevitably
there were some changes there as well:

\begin{itemize}

\item New scripts \cmdname{texconfig-sys}, \cmdname{updmap-sys}, and
      \cmdname{fmtutil-sys} were introduced, which modify the
      configuration in the system trees.  The \cmdname{texconfig},
      \cmdname{updmap}, and \cmdname{fmtutil} scripts now modify
      user-specific files, under \dirname{$HOME/.texlive2005}.
      See section~\ref{sec:texconfig}, \p.\pageref{sec:texconfig}.

\item Corresponding new variables \envname{TEXMFCONFIG} and
      \envname{TEXMFSYSCONFIG} to specify the trees where configuration
      files (user or system, respectively) are found.  Thus, you may
      need to move personal versions of \filename{fmtutil.cnf} and
      \filename{updmap.cfg} to these places; another option is to
      redefine \envname{TEXMFCONFIG} or \envname{TEXMFSYSCONFIG} in
      \filename{texmf.cnf}. In any case the real location of these files
      and the values of \envname{TEXMFCONFIG} and \envname{TEXMFSYSCONFIG}
      must agree.
      See section~\ref{sec:texmftrees}, \p.\pageref{sec:texmftrees}.

\item Last year, we kept \verb|\pdfoutput| and other primitives undefined
      for DVI output, even though the \cmdname{pdfetex} program was
      being used.  This year, as promised, we undid that compatibility
      measure.  So if your document uses \verb|\ifx\pdfoutput\undefined|
      to test if PDF is being output, it will need to be changed.  You
      can use the package \pkgname{ifpdf.sty} (which works under both
      plain \TeX\ and \LaTeX) to do this, or steal its logic.

\item Last year, we changed most formats to output (8-bit) characters as
      themselves (see previous section).  The new TCX file
      \filename{empty.tcx} now provides an easier way to get the
      original \verb|^^| notation if you so desire, as in:
\begin{verbatim}
latex --translate-file=empty.tcx yourfile.tex
\end{verbatim}

\item The new program \cmdname{dvipdfmx} is included for translation of
      DVI to PDF; this is an actively maintained update of
      \cmdname{dvipdfm} (which is also still available for now, though
      no longer recommended).

\item The new programs \cmdname{pdfopen} and \cmdname{pdfclose} are included
      to allow reloading of pdf files in the Adobe Acrobat Reader without
      restarting the program.  (Other pdf readers, notably \cmdname{xpdf},
      \cmdname{gv}, and \cmdname{gsview}, have never suffered from this
      problem.)

\item For consistency, the variables \envname{HOMETEXMF} and
      \envname{VARTEXMF} have been renamed to \envname{TEXMFHOME} and
      \envname{TEXMFSYSVAR}, respectively.  There is also
      \envname{TEXMFVAR}, which is by default user-specific.  See the
      first point above.

\end{itemize}


\subsection{Present}
\label{tlcurrent}

In 2006--2007, the major new addition to \TL{} was the Xe\TeX{} program,
available as the \texttt{xetex} and \texttt{xelatex} programs; see
\url{http://scripts.sil.org/xetex}.

MetaPost also received a notable update, with more planned for the
future (\url{http://tug.org/metapost/articles}), likewise pdf\TeX{}
(\url{http://tug.org/applications/pdftex})

The \TeX\ \filename{.fmt} (high-speed format) and the similar files for
MetaPost and \MF\ are now stored in subdirectories of \dirname{texmf/web2c},
instead of in the directory itself (although the directory is still
searched, for the sake of existing \filename{.fmt}'s).  The
subdirectories are named for the `engine' in use, such as \filename{tex}
or \filename{pdftex} or \filename{xetex}.  This change should be
invisible in normal use.

The (plain) \texttt{tex} program no longer reads \texttt{\%\&} first
lines to determine what format to run; it is the pure Knuthian \TeX.
(\LaTeX\ and everything else do still read \texttt{\%\&} lines).

The installation scripts now accept various environment variables to
allow for non-interactive installation; see
section~\ref{sec:noninteractive-install}.

Of course the year also saw (the usual) hundreds of other updates to
packages and programs.  As usual, please check \acro{CTAN}
(\url{http://www.ctan.org}) for updates.

Internally, the source tree is now stored in Subversion, with a standard
web interface for viewing the tree, as linked from our home page.
Although not visible in the final distribution, we expect this will
provide a stable development foundation for future years.

Finally, in May 2006 Thomas Esser announced that he would no longer be
updating te\TeX{} (\url{http://tug.org/tetex}).  As a result, there was
been a surge of interest in \TL{}, especially among \acro{GNU}/Linux
distributors.  (There is a new \texttt{tetex} installation scheme in
\TL{}, which provides an approximate equivalent.)  We hope this will
eventually translate to improvements in the \TeX\ environment for
everyone.


\subsection{Future}

\emph{\TL{} is not perfect!}  (And never will be.)  We intend to
continue to release new versions, and would like to provide more help
material, more utilities, more installation programs, and (of course) an
ever-improved and better-checked tree of macros and fonts. This work is
all done by hard-pressed volunteers in their limited spare time, and a
great deal remains to be done. If you can help, please put your name
forward.

Please send corrections, suggestions, and offers of help to:\hfill\null
\begin{quote}
\email{tex-live@tug.org} \\
\url{http://tug.org/texlive}
\end{quote}

\medskip
\noindent \textsl{Happy \TeX ing!}

