If you don't wanna read from the files on the command line, why are you using <>? 

#!/usr/bin/perl

# usage:
#   myscript *.txt
#   myscript `ls *.txt`
#   ls *.txt | myscript

use strict;
use warnings;

my @files = @ARGV;

if (!-t STDIN) {
   while (<STDIN>) {
      chomp;
      push @files, $_;
   }
}

...

[download]

But do you really need this whole STDIN thing? 

#!/usr/bin/perl

# usage:
#   myscript *.txt
#   myscript `ls *.txt`

use strict;
use warnings;

my @files = @ARGV;

...

[download]

I must agree on the previously stated point that this is not how unix filters work.

In reply to Re: Writing unix-style filters by ikegami
in thread Writing unix-style filters by njcodewarrior

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