Advertisement

04.17.2008 at 09:20AM PDT, ID: 23331519
[x]
Attachment Details
[x]
The Solution Rating System

With so many solutions, how can you tell which solutions are most likely to help you and which ones are not? To provide you with a tool to use, we rate our solutions based on various elements that most accurately determine if a solution is a quality solution. To explain what factors affect the solution rating, here are the elements we take into consideration when formulating our solution rating.

  • The Grade of the Solution
  • The Zone Rank of the Expert Providing the Solution
  • The Number of Author and Expert Comments
  • The Number of Experts Contributing
  • The Feedback of the Community

Your Input Matters
Because of the way the system is set up, the most important variable in this equation is you. As a member of Experts Exchange, you are able to cast your vote on the quality of the solutions in regard to how complete, accurate, helpful and easy to understand each solution is. When you provide your feedback, each rating is adjusted accordingly. So, if you see a solution that has a poor rating that you think is a good solution, let us know by rating it. As you do, the rating will be adjusted and will become more accurate for other members of our site.

If you have any suggestions that you would like to make for our rating system, please ask a question in the Suggestions Zone of Community Support.

Thank you!

8.9

Forks with sockets, hitting an unknown wall?

Asked by dr34m3rs in Perl Programming Language, Linux Networking

Tags:

If I run more than 40 forks it prints out nothing... however if I run it with 40 or less it prints out the expected outputs. I would like to be able to get an error message or something as to why it prints out nothing.

Running this on a linux machine with ulimits turned all the way up for testing purposes...Start Free Trial
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
#!/usr/bin/perl
 
use strict;
use warnings;
use Socket;
 
my $oct = "0.0.0."; # change this to first 3 octets of an address with a "." on the end
my $port = 80;
 
my $count = 0;
while($count < 40)
{
	$count++;
	
	my $host = "$oct$count";
	
	if(fork)
	{
		my $error = 0;
		my $sin = "";
		eval
		{
			socket(SH, PF_INET, SOCK_STREAM, getprotobyname('tcp')) || die $!;	
			$sin = sockaddr_in ($port,inet_aton($host)) || die $!;
		}; if($@){ print $@."\n";}
		eval
		{
			local $SIG{ALRM} = sub { die "alarm clock restart" };
			alarm 3; #10 seconds to establish the connection
			if (connect(SH,$sin))
			{
				print $host." on port ".$port." OPEN\n";
			}
			else
			{
				print "Unable to connect to $host on port $port: ".$!."\n";
				alarm 0; #reset the alarm
			}
		};
		if ($@ and $@ !~ /alarm clock restart/)
		{
			print "Connection timed out for $host on port $port\n";
		}
		
		close(SH) || die $!;
		
		exit 0;
	}
}
 
exit 0;
 
Keywords: Forks with sockets, hitting an unkno…
 
Loading Advertisement...
 
[+][-]04.17.2008 at 09:27AM PDT, ID: 21378840

View this solution now by starting your 7-day free trial. Setting up your free trial is quick, easy, and secure. We will return you to this solution, unlocked, when you're done.

 

About this solution

Zones: Perl Programming Language, Linux Networking
Tags: Perl
Sign Up Now!
Solution Provided By: Adam314
Participating Experts: 1
Solution Grade: A
 
 
[+][-]04.17.2008 at 10:22AM PDT, ID: 21379338

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 7-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]04.17.2008 at 10:28AM PDT, ID: 21379376

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 7-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]04.17.2008 at 10:35AM PDT, ID: 21379428

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 7-day free trial to view this Author Comment or ask the Experts your question.

 
[+][-]04.17.2008 at 10:46AM PDT, ID: 21379516

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 7-day free trial to view this Author Comment or ask the Experts your question.

 
 
Loading Advertisement...
20080716-EE-VQP-32 / EE_QW_2_20070628