greppy - Save grep matched and not matched lines to different files

greppy

#!/usr/bin/env perl

#	= ^ . ^ =
# greppy - Save grep matched and not matched lines to STDOUT and STDERR
# Andres Hernandez - tonejito
#
# https://gist.github.com/tonejito/c9c0bffd75d8c81483f9107c609439e1
#
# This script is released under the BSD 3-clause license
# https://opensource.org/licenses/BSD-3-Clause

use strict;
use warnings;

my $HELP = "
Usage:	$0 regex 0< STDIN 1> STDOUT 2> STDERR

  regex		Perl-compatible regular expression
  STDIN		Input file
  STDOUT	Matched lines
  STDERR	Not matched lines
" ;

die $HELP.'\n' unless ( @ARGV > 0 );

while(<STDIN>)
{
  if ($_ =~ /$ARGV[0]/)
  {
    print STDOUT $_;
  }
  else
  {
    print STDERR $_;
  }
}