os.path.exists() for files in your Path?

Question

I commonly use os.path.exists() to check if a file is there before doing anything with it.

I\'ve run across a situation where I\'m calling a executable that

Answer 1

You could get the PATH environment variable, and try "exists()" for the .exe in each dir in the path. But that could perform horribly.

example for finding notepad.exe:

import os
for p in os.environ["PATH"].split(os.pathsep):
    print os.path.exists(os.path.join(p, 'notepad.exe'))

more clever example:

if not any([os.path.exists(os.path.join(p, executable) for p in os.environ["PATH"].split(os.pathsep)]):
    print "can't find %s" % executable

Is there a specific reason you want to avoid exception? (besides dogma?)