Go4Expert - Paths in Perl

Different Operating Systems use different characters as their path separator when specifying directory and file paths:

foo/bar/baz # *nix uses a /
foo\bar\baz # Win32 uses a \
foo:bar:baz # Mac OS 9 uses a :
foo/bar/baz # Mac OS X uses a / (usually!)

In Perl you can generally just use a / as your path separator (except on Mac OS 9, thanks Hanamaki). Why? Because Perl will automagically convert the / to the correct path separator for the system it is running on! This means that coding Windows paths like this

$path = "\\foo\\bar\\baz";

is not required. You can just use this:

$path = "/foo/bar/baz";

and things will be fine. In fact using \\ can be problematic, but you probably already know that :-)

If you want to display the expected system delimiter to a user (ie hide the fact that you are using / internally) you can just do something like this:

Code: PERL

my $perl_path = '/foo/bar/baz';
 (my $win_path = $perl_path) =~ tr!/!\\!;
 print "Perl still sees: $perl_path\n";
 print "But we can print: $win_path\n";

If you need to do lots of conversions just write a sub like this:

Code: PERL

my $perl_path = '/foo/bar/baz';
 print "This is the Windows path: ", win_path
 ($perl_path), "\n";
 
 sub win_path {
 (my $path = shift) =~ tr!/!\\!;
 return $path;
 }

So there you have it. Paths in Perl. By using a / you make it much easier to port your code to another system.