On windows, I'd use xcopy /exclude:fileOfThingsToExclude src dst

Yes, but when I do this from perl, my program would not be portable to other platforms anymore.

There are usually so many special cases to be dealt with when dealing with filesystems, that it doesn't make sense to try and use the same code on Win32 and *nix-like systems. So don't try:

if( $^O eq 'mswin32' ) {
     ## use xcopy
}
elsif( $^O =~ m[(linux|unix|whatever)] ) {
     ## use something else
}
else {
    ## use another something else
    ## or throw up your hands in disgust.
}
[download]

What do I mean by special cases?

1. *nix filesystems have:
   • a unified filespace;
   • soft & hard links;
   • chmod, chown, chgrp;
   • case-sensitivity;
   • Unicode filenames?;
   • other;
2. Win32 filesystems have:
   • drives;
   • UNCs;
   • shares;
   • substs;
   • junctions;
   • streams;
   • attributes;
   • ACLs;
   • case-transparency;
   • long & short filenames;
   • Wide-character filenames;
   • other;
3. Other non-disish/non-*nixish filesystems?

   ...

Mixing all the special cases together and trying to deal with them in-line, is an exercise in frustration & complexity and is doomed to years of bugs and failures.

Make a high-level, up-front decision as to which system you are on and then load a different module or use a different subroutine and keep the logic simple(r).

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