Hello finddata

I think everyone is trying to explain that the way that you have defined your regular expression will not work. The reason:

foreach my $temp_line(@store_files)
{
if(my $pattern =~ /^REVISION_LOCATION:/){
[download]

Simply you are comparing against an empty string. It is like you are doing if('' =~ /^REVISION_LOCATION:/){, when you should be doing something like: if($temp_line =~ /^REVISION_LOCATION:/){.

If still is not clear enough read the perlrequick it will give a quick understanding about regex.

Sample of replicating your error:

#!/usr/bin/perl
use strict;
use warnings;

my $dir = shift // '.';
opendir my $dh, $dir
    or die "Could not open '$dir' for reading '$!'\n";
my @things = grep {$_ ne '.' and $_ ne '..'} readdir $dh;

foreach my $thing (@things) {
    if(my $pattern =~ /^test/){
    print $thing . "\n";
    }
}
closedir $dh
    or die "Could not close dir hanlde '$dh': '$!'\n";

__END__

Monks$ perl test.pl
Use of uninitialized value $pattern in pattern match (m//) at test.pl 
+line 11.
Use of uninitialized value $pattern in pattern match (m//) at test.pl 
+line 11.
[download]

I would also recommend to refactor a bit your code an use readdir .

Sample from my localhost with no error:

#!/usr/bin/perl
use strict;
use warnings;

my $dir = shift // '.';
opendir my $dh, $dir
    or die "Could not open '$dir' for reading '$!'\n";
my @things = grep {$_ ne '.' and $_ ne '..'} readdir $dh;

foreach my $thing (@things) {
    if($thing =~ /^test/){
    print $thing . "\n";
    }
}
closedir $dh
    or die "Could not close dir hanlde '$dh': '$!'\n";

__END__

Monks$ perl test.pl
test.pl~
test.pl
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