Re: Scanning Environment Variables

The application is JAM, which is a make replacement. It needs to scan the
environment to establish the initial control variable state (CC and the like).
I have not read the code too closely, so I am not sure if I could rework its
search functions to access the environment variables one at time using the
runtime library routine.

The 2.6.2 GNU C driver (gcc) also accesses the enivornment in a fashion similar
to JAM, so I imagine there may be other applications that need this facility.

A shell script could work, but I find it rather clumsy. I would much rather
have some iterator routines that could walk the environment, much like the
dirent routines allows me to walk directory trees.

An aside: I find the idea of a tree-structured environment to be quite
fascinating. My current customer uses a very complex set of macros to set up
an operating environment for the various revisions of their product. Having a
set of parallel environments, one for each different configuration, would be a
real boon. To switch environment, I would only need to move to a different
point in the tree. The tree structured environment is so direct and so simple,
and yet quite flexible, that I am going to spend more time to study it.

-- 
David Koogler (koogler@bedford.progress.com)