It has been a long time since I've had to write a Perl program that had to support an OS other than Linux/Unix/POSIX, MS Windows and Mac OSX.

Internally, MS Windows accepts / as a path separater. It is cmd.exe that has a problem because it treats / as the option introducer. So, c:/path/to/file or even c:\path\to/file are valid.

Of course, Linux/etc and Mac OSX don't use volume designaters ("drive letters"), so would try to treat "c:" as a directory in the current directory, but, so far, in the Perl programs I've written, the only source of volume designaters is from user input (either directly or through a file dialog box).

In the rare case I have to start cmd.exe from Perl, I have used File::Spec::canonpath to insure the file path is acceptable.

Otherwise, I usually treat file paths as POSIX style and have no problems.

For example, to split a path, I just use

@dirs = split qr{[\\/]}, $path;
$file = pop @dirs unless -d $path;
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And to assemble a path

$path = '/' . join '/', @dirs, ($file // '');
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Mostly, I don't care about the volume. If I need it, it's in $dirs[0].