open (FIND_CMD, "find /home/modules |");
chomp (my @findArr = <FIND_CMD>);

##</code><code>##

my $pattern = '.pm$';
my $FilePattern = "sub user_method";
my $ResultFilePath = '/tmp/ModuleSearch';

foreach my $File ( @findArr )
{
   next if ( $File !~ m/$pattern/ );

##</code><code>##

   system ("grep -iHl \"$FilePattern\" \"$File\" >> $ResultFilePath ");

##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;

open my $find, '-|', 'find /home/modules -name "*.pm"' or
  die "Can't run find(1): $!\n";

$\="\n";
while (<$find>) {
    chomp;
    open my $fh, '<', $_ or
      die "Can't open `$_': $!\n";
    while (my $line=<$fh>) {
        print, last if $line =~ /sub user_method/;
    }
}

__END__

##</code><code>##

#!/usr/bin/perl  -ln

use strict;
use warnings;

BEGIN { @ARGV='find /home/modules -name "*.pm"|' }

local @ARGV=$_;
/sub user_method/ and (print $ARGV), last while <> ;

__END__