If you need to change the path separator based on underlying OS, File::Spec's catfile and catdir should help. It's a standard module, and its purpose is to "portably perform operations on file names".

An example:

#!perl
use File::Spec::Functions;
print catfile( qw/dir subdir file/ );
__END__
On my FreeBSD box, the result is "dir/subdir/file"
On my Win2K box  , the result is "dir\subdir\file"
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