I recommend doing this in your for loop. Instead of:

for (@ARGV) { }
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Use:

for ( grep {-f $_} map{ glob($_) } @ARGV ) { }
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This will, in a cross-platform way, return a list of all files in the directory. If you need things that aren't files (like directories), you can drop the grep {-f $_} piece.

See glob, grep, and map for more.