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NAME
tex, initex, virtex - text formatting and typesetting
SYNOPSIS
tex [ first line ]
initex [ 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 by
Donald E. Knuth, published by Addison-Wesley.
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 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 file name 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 file names. If TeX doesn't get a file name 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 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 /usr/lpp/tex/inputs
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 hardly ever necessary 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.
Several environment variables can be used to set up
directory paths to search when TeX opens a file for input.
For example, the csh command
setenv TEXINPUTS .:/usr/me/mylib:/usr/lpp/tex/inputs
or the sh command sequence
TEXINPUTS=.:/usr/me/mylib:/usr/lpp/tex/inputs
export TEXINPUTS
would cause all invocations of TeX and its derivatives to
look for \input files first in the current directory, then
in a hypothetical user's ``mylib'', and finally in the
system library. Normally, you would place the variable
assignment which sets up the TEXINPUTS environment variable
in your .login or .profile file. The environment variables
section below lists the relevant environment variables, and
their defaults.
The e response to TeX's error prompt causes the system
default editor to start up at the current line of the
current file. There is an environment variable, TEXEDIT,
that can be used to change the editor used. It should
contain a string with "%s" indicating where the filename
goes and "%d" indicating where the decimal linenumber (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 file name;
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 file name as
the first thing it reads. A format file name is preceded by
an &, which needs to be escaped with \ to prevent
misinterpretation by your 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 by a symbolic link in a privately maintained path
ln -s /usr/bin/virtex mytex
in a directory such as /home/me/bin.
Another approach is to set up a alias using, for example,
the C shell:
alias mytex virtex \&myfmt
Besides being more cumbersome, however, this approach is not
available to systems which do not accept aliases. Finally,
there is the system known as ``undump'' 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 enormous amounts of disk space.
ENVIRONMENT VARIABLES
The defaults for all environment variables are set at the
time of compilation in a file named site.h in the web2c
distribution. All paths are colon-separated. If you set an
environment variable to a value that has a leading colon,
the system default shown here is prepended. Likewise for a
trailing colon. For example, if you say
setenv TEXFONTS :/u/karl/myfonts
TeX will search
Furthermore, the person who installed TeX at your site
may have chosen to allow one level of subdirectories to be
searched automatically (by defining the symbol
SEARCH_SUBDIRECTORIES in site.h). In that case,
subdirectories of directories in the environment variable
TEXFONTS_SUBDIR are also searched for fonts, and
subdirectories of directories in the environment variable
TEXINPUTS_SUBDIR are also searched for input files. All the
programs in the base TeX distribution 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 texpaper and the
current directory is not writable, and 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 ``.''. Default:
.:/usr/lpp/tex/inputs.
TEXINPUTS_SUBDIR
Search path for directories with subdirectories of
input files. Default: @TEXINPUTS_SUBDIR@
TEXFONTS
Search path for font metric (.tfm) files. Default:
/usr/lpp/tex/fonts.
TEXFONTS_SUBDIR
Search path for directories with subdirectories of
fonts. Default: @TEXFONTS_SUBDIR@
TEXFORMATS
Search path for format files. Default:
/usr/lpp/tex/formats.
TEXPOOL
Search path for INITEX internal strings. Default:
/usr/lpp/tex/pool.
TEXEDIT
Command template for switching to editor. Default:
/usr/bin/vi+%d%s.
FILES
/usr/lpp/tex TeX's library areas
/usr/lpp/tex/pool/tex.pool
Encoded text of TeX's messages.
/usr/lpp/tex/fonts/*.tfm
Metric files for TeX's fonts.
/usr/lpp/tex/fonts/*nnn{gf,pk}
Bitmaps for various devices. These
files are not used by TeX.
/usr/lpp/tex/formats/*.fmt
TeX .fmt files.
/usr/lpp/tex/inputs/plain.tex
The ``default'' macro package.
SEE ALSO
Donald E. Knuth, The TeXbook
Leslie Lamport, The LaTeX Document Preparation System
Michael Spivak, The Joy of TeX
TUGBOAT (the publication of the TeX Users Group)
TRIVIA
TeX, pronounced properly, rhymes with ``blecchhh.'' Note
that the proper spelling in typewriter-like media 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,
written by Tomas Rokicki and Tim Morgan.