I am trying to create a script that shows lines in one file that are in another file. Like this: 
use strict;
use strict;
use warnings;

my %file2;
open my $file2, '<', '/tmp/dog.txt' or die "Couldn't open file2: $!";
while ( my $line = <$file2> ) {
    ++$file2{$line};
}

open my $file1, '<', '/tmp/cat.txt' or die "Couldn't open file1: $!";
while ( my $line = <$file1> ) {
    print $line if $file2{$line};
}

[download]
dog.txt
ARF
police
set

cat.txt
meow
arf
police

[download]
The script correctly returns "police." But the problem is that I have 50 files like this & I need to assign files to a variable so that it can compare one file to another. Does anyone know how to get multiple files in a script like this? so there may be horse.txt and lama.txt and camel.txt and tiger.txt and I want to check each file against dog.txt and cat.txt. Is this possible? I would also like to know if part of a pattern can be compared -such as grep /poli/ - I have only been able to do it by line.

In reply to comparing multiple files for patterns by 2015_newbie

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