My question is: would it be better to have a variable passing to a lookup sub to say "this is forward" or "this is reverse"

The two subs look almost exactly the same to me, so I'd return the data from them instead of sticking it in global variables and merge the two subs into one.

Aside from unnecessary use of global variables instead of passing parameters and not using strict, I have a few small quibbles:

if ($#ARGV lt 0)
{
        &usage;
}

[download]

You probably don't want to use string comparisons where you mean numeric comparisons. Also, I personally dislike the Perl 4-style subroutine calls. I'd instead write:

usage() unless @ARGV;

You can also replace C-style loops:

for ($count=0; $count ne $#reversename; $count++) {}

with Perl style loops:

for my $count ( 0 .. $#reversename ) {}

I'd probably do the comparison while looping over IP addresses, though; there's no real need to create the arrays.

In reply to Re: code review by chromatic
in thread code review by svankalken

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