On Debian based distributions, a handy tool called dh-make-perl can be installed to ease the installation of CPAN Perl modules on the system. This tool will create a Debian package of the CPAN module, and can also install this package … Continue reading
Tag Archives: Perl
When writing Perl scripts to automate shell tasks, file handlers will be used for reading files, writing to files, executing commands, redirecting output, … But these handlers can only be opened in one direction if they are created with the … Continue reading
There are probably already 13 in a dozen applications or websites that can do this, but I wanted to write one on my own, in the programming language I like: Perl. Nowadays writing programs for tasks concerning Web 2.0 alike … Continue reading
At my daily job as a Perl developer, I was asked to write a Perl script which would download a backup file from a certain web interface. The file however, was in a secured part of the web site. This … Continue reading
Somebody once told me that a good engineer / scientist is extremely lazy. He HAS to be extremely otherwise he isn’t good. And I like being lazy (read: I love to automate repetitive tasks). Working as a contractor, we have … Continue reading
This Perl script was initially written about 3 or 4 years ago, but still does its daily job: monitor that certain processes are running and if not, restart them (plus send out a notification). The script should run as the … Continue reading
DCC is a wonderful tool, but it needs to be fed constantly. After going through the process of blacklisting a few emails that weren’t tag as spam, I found myself in a not so lazy position. We don’t like that … Continue reading
To get an overview of what is running on a certain UNIX/Linux host, most users will usually run of one the following commands: ps top htop But most of the times, they will not give a correct view of what … Continue reading
I had to mimic a certain web application for a customer I’m currently working for, so I’ve created a small standard webserver in Perl using HTTP::Daemon. The only thing it does, is serving one particular file.
This is a small code snippet I wrote along time ago for a bigger framework I’ve created. No extra modules are required. It calculates the netmask of a network based on the network address and network bit (CIDR notation).
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#!/usr/bin/perl use strict; use warnings; sub _calc_netmask { my($subnet) = @_; # e.g.: 10.0.0.0/24 192.168.1.0/16 my($network, $netbit) = split /\//, $subnet; my $_bit = ( 2 ** (32 - $netbit) ) - 1; my ($full_mask) = unpack( "N", pack( "C4", 255,255,255,255 ) ); my $netmask = join( '.', unpack( "C4", pack( "N", ( $full_mask ^ $_bit ) ) ) ); return $netmask; } foreach my $line (<DATA>){ chomp($line); printf "SUBNET: %18s | NETMASK: %15sn", $line, _calc_netmask($line); } __DATA__ 10.0.0.0/24 192.168.1.0/27 195.94.76.0/29 172.16.0.0/17 172.19.0.0/16 1.0.0.0/8 2.0.0.0/12 4.0.0.0/13 |