#!/usr/bin/perl -w

use strict;

my $pat_qfn = '30.txt';
my $in_qfn  = 'searchfile.txt';
my $out_qfn = 'newfile.txt';

my $pat;
{
    open(my $pat_fh, '<', $pat_qfn)
        or die("Can't open pattern file $pat_qfn: $!\n");

    chomp( my @pats = <$pat_fh> );

    ($pat) =
        map qr/$_/,
        join '|',
        @pats;
}

open(my $in_fh, '<', $in_qfn)
    or die("Can't open input file $in_qfn: $!\n");

open(my $out_fh, '>', $out_qfn)
    or die("Can't create output file $out_qfn: $!\n");

while (<$in_fh>) {
    print $out_fh $_ if /$pat/;
}