muconf Files

muconf is a simple program that reads from standard input,
replaces each substring of the form @IDENTIFIER@ with the value
of IDENTIFIER from the environment, and writes the result to standard output. 
If IDENTIFIER is not found in the environment then @IDENTIFIER@
is replaced with nothing and a warning is sent to stderr.

Thus

   HOME = @HOME@

is replaced with

   HOME = /Users/johndoe

for example.

muconf is useful in shell scripts which need to process files. A good
example is a configure script that checks to see what compiler or
libraries are available for a project. Of course autoconf does this
but in a much much much more complex way. A perl script could do what
muconf does, but then the project would depend on perl.

Usage:

  muconf < input > output

Note that variables must be exported for muconf to see them.

Thus in the commands

   MUTEST=blarg
   muconf < test.in 

MUTEST is not exported so muconf knows nothing about it and will
complain when it is encountered.

On the other hand in the shell code

   MUTEST=blarg muconf < test.in

MUTEST is exported when the shell runs muconf and so muconf recognizes it.