Pattern Matching Again

monger has asked for the wisdom of the Perl Monks concerning the following question:

Greetings all,
I'm working on a log parsing project and am trying to modify one of the scripts, but it's giving me some fits that I can't figure out. The code:

 if (length($_)>10) {
        $readlines++;
[download]

This is the original. It's an arbitrary lenght check. If the log line is at least 10 characters, it'll pass. What I need to do is add a secondary check to verify that the log line contains one of our IP addresses. Here's what I've tried:

 if (length($_)>10) {
        if ($_ =~ (m/192\.168\./g)) {
        $readlines++;
[download]

But what happens is that I only ever have one line accepted. If I run the original script, I had 10,000 lines accepted. With this mod, the identical content only has one line accepted.
Suggestions?
Thanks,
monger

Monger +++++++++++++++++++++++++ Munging Perl on the side

Comment on Pattern Matching Again - IP Addy Select or Download Code

Replies are listed 'Best First'.
Re: Pattern Matching Again - IP Addy by ikegami (Patriarch) on Nov 17, 2004 at 21:24 UTC
hum, it works for me... `while (<DATA>) { if (length($_) > 10) { if ($_ =~ (m/192\.168\./g)) { $readlines++; } } } print($readlines, $/); # prints 3, although you're probably expecting it to be 2. __DATA__ 192.168.0.1 1.192.168.0 12345678901 dfhasfhasdjk 192.168.33.4` [download] The /g is unecessary, misleading, and a potential cause of problem. The $_ is the default argument for both length and m//, so it can be omitted: `while (<DATA>) { if (length && /192\.168\./) { $readlines++; } } print($readlines, $/); # prints 3, although you're probably expecting it to be 2. __DATA__ 192.168.0.1 1.192.168.0 12345678901 dfhasfhasdjk 192.168.33.4` [download]	[reply] [d/l] [select]
Re^2: Pattern Matching Again - IP Addy by monger (Friar) on Nov 18, 2004 at 14:50 UTC
Thanks ikegami. That did the trick! monger Monger +++++++++++++++++++++++++ Munging Perl on the side	[reply]
Re: Pattern Matching Again - IP Addy by NetWallah (Canon) on Nov 17, 2004 at 21:26 UTC
~~You are giving the regex a list context - that is messing you up.~~ Update:Nope - the RE works fine, but ikegami's is better. Earth first! (We'll rob the other planets later)	[reply]