use strict;
use warnings;



find_string {
    my ($file, @strings) = @_;
    open my $fh, '<', $file;
    my $re = join "|", map quotemeta, @strings;
    while (<$fh>) {
        return 1 if /$re/;
    }
    die "Unable to find string: $string";
}

find_string('prepos.config', "testing","link","100K");