I think you want to use chdir to change into the directory you want.
Using opendir, you can do like so: 

use warnings;
use strict;

print "Enter a directory:";
chomp( my $dir = <STDIN> );

print "String looked for: ";
chomp( my $str = <STDIN> );

chdir $dir or die $!;

opendir DH, $dir or die $!;
while ( readdir(DH) ) {
    next if $_ eq '.' or $_ eq '..';
    unless (-d) {
        open my $fh, '<', $_ or die $!;
        while (<$fh>) {
            print $_ if /\Q$str/;
            last;
        }
    }
}
closedir DH or die $!;

[download]
I also think, it would be great if you can open the files one after the other immediately and check for desired string.

If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: Perl script does not work on other directories? by 2teez
in thread Perl script does not work on other directories? by Anonymous Monk

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