message upon not finding the file

[Dan Jacobson]

perl doesn't say "perl:"
$ perl a
Can't open perl script "a": No such file or directory

bash doesn't say "bash", and says 'a' twice:
$ bash a
a: a: No such file or directory

Both make it tough to figure out where the message came from, when
seen amongst other messages.

Only grep gets it right
$ grep x a
grep: a: No such file or directory