Re: test for presence of library

[Harry Putnam]

Sorry for my tardy response... I got distracted for a while.

Thanks posters one and all... good suggestions and great helpful
info.  I have several solutions now.

One case, the one that actually pertains here that didn't get
mentioned by TimX is where something being required is only useful in
certain environments.. 

An example might be using emacs as root when doing system configs.

There are really quite a few aspects of emacs I'll never use in that
situation. Yet its handy to have a portable emacs that loads the stuff
I need in some environments but skips it when working as root doing
system configs.

Or maybe running emacs as user but while setting up a new os where I
won't expect many things to be available... 

In those cases the idea that things may fail down the road from not
loading certain libs is not a problem since those things will not even
be attempted.  

Now I know how to do it.

Thanks to all.