I'm writing a small Perl script that will take a large list of IP addresses ( > 100), break them down into smaller chunks, and format them for our intrustion detection system (Snort). Basicly it's a var builder (for those Snort afficianados). Problem is that it's not working right, and I or anybody else that I ask around the office knows what's wrong with it. My suspicion is that it's a "string vs integer" thing.

Here's the code bit that parses thru the array of IPs (@fred) and outputs them: 

$c = 0;
$g = 0;

foreach $w (@fred)
   {
   if ($g == 0)
      {
        print "\$g = $g and \$c = $c\n";
        @fred1 = ($varname,$c);
        $temp_var1 = join("", @fred1);
        print "var $temp_var1 [";
      }
   if ($g == 20)
      {  
        print "$w]\n";
        print "\$c = $c and \$g = $g\n";
        $c++;
        @fred1 = ($varname,$c);
        $g = 0;
        print "\$g = $g";
      }
   if ($w =~ @fred[-1])
      {
        print "$w]\n";
      }
   else
      {
        print "$w,";
        $g++;
      }
   }

[download]
$g is set to 0; it's my counter to track how many IPs I've iterated thru. The plan is at $g == 20, close the current chunk of IPs, and start a new chunk (setting $g back to 0). $c is the chunk counter; it counts how many chunks I have. Each chunk is named from a combination of a user-supplied variable name (gotten earlier in the program) and $c. Both $g and $c are set to 0 before the foreach begins. If $g is neither 0, it outputs $w (the IP address). If $w is the last element in the array, the current chunk is closed and the foreach stops.

The problem is that the first IF statement (which checks for $g == 0) is only run thru once, at the very beginning. I've outputted the values of both $g and $c after each foreach iteration, and it'll clearly say that $g = 0 after the 20th IP, then proceed to apparently fail the $g == 0 test. Since I know that 0 == 0, I'm assuming that it must be some kind of integer vs string confusion in my code.

2005-03-17 Edited by Arunbear: Changed title from 'have no idea why this isn't working', as per Monastery guidelines

In reply to Breaking up a list of IP addresses for Snort by Chris_LSU

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