iso: info on determining in what packages a command might be found?

I'm working on a project to port an application from sparc solaris to intel
redhat linux.

One of the shell commands that make up a part of this application invokes
the command 'compress' on solaris.  I know there are comperable commands like
gzip or bzip2 - but since the application is going to continue to run on
both platforms, I need to invoke compress on linux.

To do that, I need to _find_ compress.

What resources are available to 'look up' to see what red hat package contains
compress - or any other command, for that matter?
-- 
Tcl - The glue of a new generation.  <URL: http://wiki.tcl.tk/ >
Larry W. Virden <mailto:[email protected]> <URL: http://www.purl.org/NET/lvirden/>
Even if explicitly stated to the contrary, nothing in this posting should 
be construed as representing my employer's opinions.
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