Adding some test data: 
use List::Util 'shuffle';

my @fileData = shuffle map { "$_\n" } 1 .. 20, (1) x 5;

my $linenumber=1;
foreach my $line(@fileData) {
   $linenumber=$linenumber+1;
   if ($line =~ m/^1$/) {
       print "$linenumber\n";
   }
}

[download]

Output: 

6
7
8
16
17
25

[download]

Are you sure you're reading your data correctly?

In reply to Re: Help with regex by FunkyMonk
in thread Help with regex by ChuckularOne

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