Expansions in administrative files
==================================

   Sometimes in writing an administrative file, you might want the file
to be able to know various things based on environment CVS is running
in.  There are several mechanisms to do that.

   To find the home directory of the user running CVS (from the `HOME'
environment variable), use `~' followed by `/' or the end of the line.
Likewise for the home directory of USER, use `~USER'.  These variables
are expanded on the server machine, and don't get any resonable
expansion if pserver (see Password authenticated.) is in used;
therefore user variables (see below) may be a better choice to
customize behavior based on the user running CVS.

   One may want to know about various pieces of information internal to
CVS.  A CVS internal variable has the syntax `${VARIABLE}', where
VARIABLE starts with a letter and consists of alphanumberic characters
and `_'.  If the character following VARIABLE is a non-alphanumeric
character other than `_', the `{' and `}' can be omitted.  The CVS
internal variables are:

`CVSROOT'
     This is the value of the CVS root in use.  See Repository, for
     a description of the various ways to specify this.

`RCSBIN'
     This is the value CVS is using for where to find RCS binaries.
     See Global options, for a description of how to specify this.

`CVSEDITOR'
`VISUAL'
`EDITOR'
     These all expand to the same value, which is the editor that CVS
     is using.  See Global options, for how to specify this.

`USER'
     Username of the user running CVS (on the CVS server machine).

   If you want to pass a value to the administrative files which the
user that is running CVS can specify, use a user variable.  To expand a
user variable, the administrative file contains `${=VARIABLE}'.  To set
a user variable, specify the global option `-s' to CVS, with argument
`VARIABLE=VALUE'.  It may be particularly useful to specify this option
via `.cvsrc' (see ~/.cvsrc.).

   For example, if you want the administrative file to refer to a test
directory you might create a user variable `TESTDIR'.  Then if CVS is
invoked as

     cvs -s TESTDIR=/work/local/tests

and the administrative file contains `sh ${=TESTDIR}/runtests', then
that string is expanded to `sh /work/local/tests/runtests'.

   All other strings containing `$' are reserved; there is no way to
quote a `$' character so that `$' represents itself.