NAME
tex, virtex - text formatting and typesetting
SYNOPSIS
tex [ first line ]
virtex [ first line ]
DESCRIPTION
TeX formats the interspersed text and commands contained in
the named files and outputs a typesetter independent file
(called DVI, which is short for DeVice Independent). TeX
capabilities and language are described in The TeXbook.
TeX is normally used with a large body of precompiled
macros, and there are several specific formatting systems,
such as LaTeX, which require the support of several macro
files. The basic programs as compiled are called initex and
virtex, and are distinguished by the fact that initex can be
used to precompile macros into a .fmt file, which is used by
virtex. On the other hand, virtex starts more quickly and
can read a precompiled .fmt file, but it cannot create one.
It is the version of TeX which is usually invoked in
production, as opposed to installation.
Any arguments given on the command line to the TeX programs
are passed to them as the first input line. (But it is
often easier to type extended arguments as the first input
line, since Unix shells tend to gobble up or misinterpret
TeX's favorite symbols, like backslashes, unless you quote
them.) As described in The TeXbook, that first line should
begin with a filename or a \controlsequence. The normal
usage is to say
tex paper
to start processing paper.tex. The name paper will be the
``jobname'', and is used in forming output filenames. If
TeX doesn't get a filename in the first line, the jobname is
texput. The default extension, .tex, can be overridden by
specifying an extension explicitly.
If there is no paper.tex in the current directory, TeX will
look through a search path of directories to try to find it.
If paper is the ``jobname'', a log of error messages, with
rather more detail than normally appears on the screen, will
appear in paper.log, and the output file will be in
paper.dvi. The system library directory @TEXINPUTDIR@
contains the basic macro package plain.tex, described in The
TeXbook, as well as several others. Except when .fmt files
are being prepared it is unnecessary to \input plain, since
almost all instances of TeX begin by loading plain.fmt.
This means that all of the control sequences discussed in
The TeXbook are known when you invoke tex. For a discussion
of .fmt files, see below.
The e response to TeX's error prompt causes the system
default editor to start up at the current line of the
current file. The environment variable TEXEDIT can be used
to change the editor used. It can contain a string with
"%s" indicating where the filename goes and "%d" indicating
where the decimal line number (if any) goes. For example, a
TEXEDIT string for vi can be set with the csh command
setenv TEXEDIT "/usr/ucb/vi +%d %s"
A convenient file in the library is null.tex, containing
nothing. When TeX can't find a file it thinks you want to
input, it keeps asking you for another filename; responding
`null' gets you out of the loop if you don't want to input
anything. You can also type your EOF character (usually
control-D).
The initex and virtex programs can be used to create fast-
loading versions of TeX based on macro source files. The
initex program is used to create a format (.fmt) file that
permits fast loading of fonts and macro packages. After
processing the fonts and definitions desired, a \dump
command will create the format file. The format file is
used by virtex. It needs to be given a format filename as
the first thing it reads. A format filename is preceded by
an &, which needs to be escaped with \, or quoted, to
prevent misinterpretation by the Unix shell if given on the
command line.
Fortunately, it is no longer necessary to make explicit
references to the format file. The present version of TeX,
when compiled from this distribution, looks at its own
command line to determine what name it was called under. It
then uses that name, with the .fmt suffix appended, to
search for the appropriate format file. During
installation, one format file with the name tex.fmt, with
only the plain.tex macros defined, should have been created.
This will be your format file when you invoke virtex with
the name tex. You can also create a file mytex.fmt using
initex, so that this will be loaded when you invoke virtex
with the name mytex. To make the whole thing work, it is
necessary to link virtex to all the names of format files
that you have prepared. Hard links will do for system-wide
equivalences and Unix systems which do not use symbolic
links. Symbolic links can be used for access to formats for
individual projects. For example: virtex can be hard
linked to tex in the general system directory for executable
programs, but an individual version of TeX will more likely
be linked to a private version by a symbolic link:
ln -s @BINDIR@/virtex $HOME/bin/mytex
Another approach is to set up an alias using, for example,
csh(1):
alias mytex virtex \&myfmt
Besides being more cumbersome, however, this approach is not
available to systems which do not accept aliases. Finally,
there is a program known as undump(1) which takes the
headers from an a.out file (e.g., virtex) and applies them
to a core image which has been dumped by the Unix quit
signal. This is very system-dependent, and produces
extremely large files when used with a large-memory version
of TeX. This can produce executables which load faster, but
the executables also consume more disk space.
When looking for a font f, TeX (and its companion programs)
first look for a file starting with f in the various font
directories (see the next section). If no such file is
found, it then looks for a file texfonts.map in each of the
font directories in turn. Each non-blank non-comment line
of texfonts.map specifies mappings from one name to another.
(Comments start with % and continue to the end of the line.)
The target name is the first word (words are separated by
spaces or tabs) and the source name is the second.
(Subsequent words are ignored, so that information intended
for other programs can be given there.) Thus, going back to
f for a moment, if TeX reads a texfonts.map entry that looks
like g f it will then search for a font file starting with
g.
ENVIRONMENT
See the Kpathsearch library documentation (the `Path
specifications' node) for precise details of how the
environment variables are used.
One caveat: In most TeX formats, you cannot use ~ in a
filename you give directly to TeX, because ~ is an active
character, and hence is expanded, not taken as part of the
filename. Other programs, such as Metafont, do not have
this problem.
All the programs in the web2c distribution (as well as some
others) use this same search method.
Normally, TeX puts its output files in the current
directory. If any output file cannot be opened there, it
tries to open it in the directory specified in the
environment variable TEXMFOUTPUT. There is no default value
for that variable. For example, if you say tex paper and
the current directory is not writable, if TEXMFOUTPUT has
the value /tmp, TeX attempts to create /tmp/paper.log (and
/tmp/paper.dvi, if any output is produced.)
TEXINPUTS Search path for \input and \openin files.
This should probably start with ``.'', so
that user files are found before system
files. Default: @DEFAULT_TEX_PATH@
TEXFONTS Search path for font metric (.tfm) files.
Default: @DEFAULT_TFM_PATH@
TEXFORMATS Search path for format files. Default:
@DEFAULT_FMT_PATH@
TEXPOOL search path for initex internal strings.
Default: @DEFAULT_TEXPOOL_PATH@
TEXEDIT Command template for switching to editor.
Default: @EDITOR@
MAKETEXTEX Arguments to pass to the MakeTeXTeX script
before the filename to create. None by
default. (If set, also implies invoking
MakeTeXTeX.)
USE_MAKETEXTEX If set, a program MakeTeXTeX is invoked when
TeX cannot find an input file (before it
complains about ``can't find file''). If
neither MAKETEXTEX nor USE_MAKETEXTEX are
set, whether MakeTeXTeX is invoked is the
choice of installer.
MAKETEXTFM Analogous.
USE_MAKETEXTFM Analogous.
FILES
@TEXPOOLDIR@/tex.pool Encoded text of TeX's messages.
@FONTDIR@/texfonts.map Filename mapping definitions.
@FONTDIR@//*.tfm Metric files for TeX's fonts.
@FONTDIR@//*.nnn{gf,pk} Character bitmaps for various
devices. These files are not
used by TeX.
@FMTDIR@/*.fmt Predigest TeX format (.fmt)
files.
@TEXINPUTDIR@//plain.tex The basic macro package described
in the TeXbook.
SEE ALSO
mf(1), undump(1),
Donald E. Knuth, The TeXbook, Addison-Wesley, 1986, ISBN 0-
201-13447-0.
Leslie Lamport, LaTeX - A Document Preparation System,
Addison-Wesley, 1985, ISBN 0-201-15790-X.
Michael Spivak, The Joy of TeX, 2nd edition, Addison-Wesley,
1990, ISBN 0-8218-2997-1.
TUGboat (the journal of the TeX Users Group).
TRIVIA
TeX, pronounced properly, rhymes with ``blecchhh.'' The
proper spelling in typewriter-like fonts is ``TeX'' and not
``TEX'' or ``tex.''
AUTHORS
TeX was designed by Donald E. Knuth, who implemented it
using his Web system for Pascal programs. It was ported to
Unix at Stanford by Howard Trickey, and at Cornell by Pavel
Curtis. The version now offered with the Unix TeX
distribution is that generated by the Web to C system
(web2c), originally written by Tomas Rokicki and Tim Morgan.