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diff --git a/Master/texmf-dist/doc/latex/base/autoload.txt b/Master/texmf-dist/doc/latex/base/autoload.txt new file mode 100644 index 00000000000..8e3e242a19f --- /dev/null +++ b/Master/texmf-dist/doc/latex/base/autoload.txt @@ -0,0 +1,138 @@ + IMPORTANT NOTICE + This variant of LaTeX is now UNSUPPORTED but we have left its + description in this file for posterity ... enjoy! + + LaTeX on small systems: auto-loading + + 21 November 1995 + + +On some small systems (perhaps most noticeably emTeX for PCs if your +machine is unable to use the TeX386 version) LaTeX uses up a large +amount of the memory available to TeX, leaving very little for storage +of any further commands, complex text (such as tables), floats or +cross references that may occur in a typical document. Note that +these limits are built into the TeX executable and do not directly +correspond to any physical memory that your machine has installed. + +In order to help with this problem, we have produced an *experimental* +configuration of LaTeX in which certain functions are not predefined +in the format, but are loaded automatically from a style file the first +time they are used. This saves a lot of memory in the case that a +document does not use these features. + +In this release two environments are `auto-loaded' in this way, +`picture' and `tabbing', as are various bits of internal code used in +error handling, font loading and advanced page makeup. + + +MAKING THE AUTOLOAD FORMAT +========================== + +NOTE: Before you can proceed any further you *must* unpack the standard +version from unpack.ins. + +Process the file autoload.ins (with plain TeX or LaTeX, not iniTeX). + +This will produce six files: + + latexa.ltx source file for the smaller format + + And the following five package files: + + autopict.sty source for picture mode + autotabg.sty source for tabbing environment + autoerr.sty texts of most LaTeX error commands + autofss1.sty little used internal font selection commands + autoout1.sty source for \enlargethispage and related commands. + +The `latexa' format should then be made by running iniTeX on the +file `latexa.ltx'. + +To do this, follow the instructions in install.txt (and emtex.txt +etc) but replace: + `latex.ltx' and `latex.fmt' +by + `latexa.ltx' and `latexa.fmt'. + +Finally, the five files `autoxxxx.sty' should be moved to the +directory in which the other LaTeX .sty files have been placed. + + +USING THE FORMAT +================ + +The resulting format should normally be used in exactly the same way +as standard LaTeX. + +Picture mode can be used without any special commands. Since picture +mode is not pre-defined, you will notice TeX loading the `autopict' +package the first time you use \begin{picture} (or \thicklines) in a +document. This takes some time (and the name of the file being loaded +appears on the terminal) but otherwise the behaviour should be just as +with standard LaTeX. + +For instance, processing usrguide.tex (which has a picture on page 23) +produces the following terminal output: + + This is TeX, Version 3.1415 (C version 6.1) + (usrguide.tex + LaTeX2e (autoload version) <1995/06/01> + ) + (ltxguide.cls + Document Class: ltxguide 1994/12/14 Standard LaTeX class + (article.cls + Document Class: article 1995/06/05 v1.3d Standard LaTeX document class + (size10.clo))) (usrguide.aux) (OMScmr.fd) (usrguide.toc [1]) [2] [3] + [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] + [19] [20] [21] [22] (autopict.sty) [23] [24] [25] [26] [27] [28] [29] + [30] (usrguide.aux) ) + +(The output may differ on your machine due to different path names for +the files.) + + +POSSIBLE PROBLEMS +================= + +Sometimes you need to redefine a command before it is used. Clearly, if +the command is not initially defined, it cannot easily be redefined! + +As a real example, the popular `epic' package redefines some picture +mode commands, therefore to use epic it is necessary to force +picture mode to be loaded by explicitly putting in your document +\usepackage{autopict} before \usepackage{epic}. + +If a document containing \usepackage{autopict} is sent to a site using +the `full' version of LaTeX (which has picture mode defined in the +format) then this \usepackage will be silently ignored and the +document will still work correctly. + +A note to package writers: if your package depends on the picture +environment being loaded then you can avoid the user needing to add +the extra \usepackage to documents by adding \RequirePackage{autopict} +to the beginning of your package file. + +Similar comments apply to `tabbing' and the `autotabg' package. + + +INTERNAL INTERFACE +================== + +Most new features added in LaTeX2e that were not in LaTeX2.09 have a +consistent interface of commands \WithMixedCase names. + +If you inspect the implementation of this auto-loading feature you will +not find any such interface, but rather an ad hoc collection of low- +level TeX commands. + +This situation may change as more practical experience is gained with +the auto-loading feature. In future releases it may be possible to +auto-load more parts of LaTeX (so making an even smaller `base' format) +and an interface for producing the auto-loaded files may be defined. + +However, for the user, the nature of the implementation should not +matter too much since in the normal case the loading of the file is +`invisible' and happens automatically the first time it is needed. + +--- Copyright 1995 the LaTeX3 project. All rights reserved --- |