http://invisible-island.net/
Copyright © 1996-2011,2013 by Thomas E. Dickey
conflict displays conflicting filenames in your execution path. Unlike the csh command which, it displays all of the conflicting (non-alias) executable filenames in your path.
I wrote this in 1988, based on a script that I wrote while at the ITT Advanced Technology Center to analyze execution-path and environment conflicts on VM/SP CMS. Since then, I've added the ability to scan for different types of conflicts (e.g., along an include-path for C compilers).
See the changelog for details.