Hello catfish1116,

Fellow Monks already told you the problem to your script. I would also to add a minor modification to possibly use a module IO::All so you do not need to bother with this minor issues and minimize your code on this part.

Sample of modification below:

#!/usr/bin/perl
use strict;
use warnings;
use IO::All;
use v5.16;
##############
##  03/14/19
##  Exercise reads from file, then lets user interactively submit matc
+hing search criteria

die "Please provide a file to process!\n" unless (defined $ARGV[0]);

my @lines = io($ARGV[0])->chomp->slurp;      # Chomp as you slurp

while (1) {
    print 'Please enter a pattern: ';
    chomp(my $pattern = <STDIN>);
    last if $pattern =~ /\A\s*\Z/;
    my @matches = eval {
    grep /$pattern/, @lines;
    }; ## end of eval
    if ($@) {
    print "Error: $@";
    } else {
    my $count = @matches;
    print "There were $count matching strings:\n",
        map "$_\n", @matches;
    }
    print "\n";
}
[download]

Hope this helps, BR.