use strict;
use warnings;
use diagnostics;
use File::Slurp;

my @files = read_dir($ARGV[0]); #read files in dir into an array
my $dir = $ARGV[0];

my $string = $ARGV[1];

my $file;
my $line;

foreach my $element (@files) {
    open $file, '<', "$dir/$element"; #open each file

		while (<$file>) {
			if ( $_ =~ $string ) { #match your string
				print "found $string in $element\n";
			}
		}
    close $file;
}