[PATCH build] List environment variables with usage.

[Trevor Woerner]

On Sat, Aug 7, 2010 at 9:32 AM, Gaetan Nadon <memsize at videotron.ca> wrote:
> Shouldn't the list also includes:
>
> ACLOCAL		line 792
> MAKE		line 812
> FONTPATH	line 817
>
> PKG_CONFIG_PATH	line 800
> LD_LIBRARY_PATH	line 805
> PATH		line 809

Actually, ACLOCAL, MAKE, and FONTPATH follow the same pattern and I
was going to add them to the usage() information. In other words,
defining those in the environment causes the specified commands to run
instead of the defaults. They replace the default.

PKG_CONFIG_PATH, LD_LIBRARY_PATH, and PATH don't follow the same
pattern in that they add to such-named variables; they don't replace
them. So I wasn't going to add them to the list. But I could add them
to a separate list.