Isn't there a $variable already that's specifically the path separator?
What I see is core Perl: use Config; ... $Config{"path_sep"} ... I thought we had one. The above is not currently used anywhere in Automake. There are pervasive uses of $PATH_SEPARATOR in shell code, but no determination of the path separator in Perl code that I can see. Check in Perl's built-in Config module Indeed. I guess {path_sep} has been available forever, but I still fear breaking new ground. Also, since the Config module is based on the compile-time Configure output, there are warnings that it "cannot always be trusted". Maybe it would never come up for Automake, but then again, maybe it would. as well as automaker proper. Nothing in Automake::Config or anything else that I can find. I have to admit I am tempted to just match $^O and be done with it, instead of using something that could lead to more problems in the future. From what I've seen of other code, using $^O is a lot more common than using $Config. (Anecdotally speaking.) --thanks, karl.