Sunday, November 23, 2008

Perl: How to Set Up a UDP Server

You want to write a UDP server,
First bind to the port the server is to be contacted on. With IO::Socket, this is easily accomplished:
use IO::Socket;
$server = IO::Socket::INET->new(LocalPort => $server_port,
Proto => "udp")
or die "Couldn't be a udp server on port $server_port : $@\n"; read more..

Perl : Gathering Output from a Program

The backticks are a convenient way to run other programs and gather their output. The backticks do not return until the called program exits. Perl goes to some trouble behind the scenes to collect the output, so it is inefficient to use the backticks and ignore their return value: read more...

Booting Debian in 14 seconds

This article assumes that you're already familiar with things like building kernels, applying patches and so on. The target audience is the "advanced end user", and also the Debian developers responsible for the packages concerned who I hope will be motivated to incorporate some of this work.

The AIX administrators guide to learning Linux

Most system administrators planning to install Linux® on IBM® System p® eventually run into an important question: Which Linux distribution should I install? This article compares two distributions from Red Hat and Novell, and weighs the pros and cons of each. We'll discuss Linux on POWER (LoP), the history of both distributions, the relationship IBM has with them, and the factors that should go into your decision-making process. We're also going to compare and contrast what it takes to create logical volumes on SLES and RHEL.

GCC hacks in the Linux kernel

GCC and Linux are a great pair. Although they are independent pieces of software, Linux is totally dependent on GCC to enable it on new architectures. Linux further exploits features in GCC, called extensions, for greater functionality and optimization. This article explores many of these important extensions and shows you how they're used within the Linux kernel.

Saturday, November 15, 2008

Restoring iptables Automatically On Boot

There used to be a script to do it automatically via init.d files, but now the suggested method is to use ifup.d networking scripts, which are executed on state changes of the network interfaces. So I submit here my simple script, which does the trick for me nicely.

know GCC 4

In the last few years, the GNU Compiler Collection (GCC) has undergone a major transition from GCC version 3 to version 4. With GCC 4 comes a new optimization framework (and new intermediate code representation), new target and language support, and a variety of new attributes and options. Get to know the major new features and their benefits.

Monday, November 03, 2008

Linux Pipes

A pipe is a communication device that permits unidirectional communication. Data written to the "write end" of the pipe is read back from the "read end." Pipes are serial devices; the data is always read from the pipe in the same order it was written. Typically, a pipe is used to communicate between two threads in a single process or between parent and child processes, more...