The only special problems in using LATEX caused by the UNIX operating system involve the way UNIX handles files. The first problem arises because, when a program starts to write a file, UNIX destroys the previous version of that file. Thus, if an error forces you to stop LATEX prematurely (by typing Control-C or Control-Z), then the files that LATEX was writing are incomplete, and the previous complete versions have been destroyed. You probably don't care about the output on the dvi file, but, if you are making a table of contents or using cross-referencing commands, then LATEX also writes one or more auxiliary files that it reads the next time it processes the same input file. If the auxiliary files are incomplete because LATEX was stopped before reaching the end of its input file, then the table of contents and cross-references will be incorrect the next time LATEX is run on the same input file. You will have to run LATEX a second time to get them right. If you want to avoid having to run LATEX twice after making an error--for example, if your input is very long--then you should save copies of these auxiliary files before running LATEX. An input file named myfile.tex and all the auxiliary files produced by LATEX from it are included in the UNIX file specifier myfile.*. Use the UNIX cp command to save copies of these files.
The second problem in using LATEX on UNIX involves the files that
LATEX reads. The file whose name you type with UNIX's latex
command is called the root file. In addition to reading the root
file, LATEX also reads the files specified by
\include commands. With the UNIX directory system,
LATEX must know not only the names of these files but also in what
directories they are. It will have no problem finding the correct
files if you follow two simple rules:
\includecommands in the same directory as the root file.
You should never break the first rule, otherwise LATEX will have
trouble finding auxiliary files. (To run LATEX on someone else's
file, copy the file to your directory.) If you break the second
rule, specifying a file from another directory in an
\include command, you must use a
complete path name. For example, to include the file hisfile.tex
from Jones' directory
/foo/bar, you can type
~character may not appear in the argument of an
\includecommand, so you can't use a file name such as
For people who don't like to obey rules,
here is exactly how LATEX finds its
files. The root file is found by UNIX according to its usual rules.
LATEX's auxiliary files are read and written in the directory from
which it is run. All file names specified in the LATEX input,
including the names of document-style (sty) files specified by
\documentstyle command, are interpreted relative to
the directory from which LATEX is run. If LATEX does not find a
file starting in this directory, it looks in the system directory
/usr/physics/lib/tex. You can change the directories in
which LATEX looks for its input files by setting the environment
variable TEXINPUTS. Putting the command
setenv TEXINPUTS :.:/home-theory/jones/myown:/usr/physics/lib/tex:in your .login file causes LATEX to look for files first in the current directory, then in Jones' myown directory, and then in the system directory. You might want to do this if your name is Jones and you have your own personal document-style files in your myown directory.