Copyright © 2008, 2009, 2010 Marc Balmer. All rights reserved.
Decoding the DCF77 and HBG Time Signal Stations Using OpenBSD
Sat, 2007/12/22 - 12:19 — Marc BalmerMarc Balmer
Copyright (C) 2006 Marc Balmer
Every computer is equipped with at least a clock chip or a general purpose device to provide a timer function. While these timers are certainly precise enough for measuring relatively short periods of time, they are not well suited for keeping the correct time and date over a longer period, since almost every chip drifts by a few seconds per day. Even so called real-time clocks only approximately meet the real time.
Time signal stations can be a solution to this problem as they emit very precise time information using specifically modulated radio frequencies. Time signal stations are available in many countries; while the coding schemes vary from time signal station to time signal station, the decoding principles are similar.
Using OpenBSD's chrooted httpd
Sat, 2007/12/22 - 11:52 — Marc BalmerCopyright © 2003-2008 by Marc Balmer. All rights reserved.
OpenBSD some time ago changed the mode of operation for the Apache webserver from the normal non-chrooted operation to chrooted operation. This enhances the security of the server on which Apache is run but it imposes a few challenges to the system administrator.
In this article I will discuss selected aspects of running a chrooted HTTP daemon and present strategies on how to set up a chrooted environment for more complex applications like database access or using CGI-scripts.
(First published on April 6, 2003, revised on March 20, 2004, converted to HTML for online publishing on December 21, 2007.)
Using Java for CGI Applications
Mon, 1996/01/01 - 02:00 — Marc BalmerCopyright © 1996 by Marc Balmer, CH-4055 Basel, Switzerland.
This paper discusses strategies and methods to use Java as a programming language for CGI (Common Gateway Interface) applications.
The Java Framework for CGI
Mon, 1996/01/01 - 01:00 — Marc Balmer(This document describes version 1.01 of the framework)
Copyright © 1996 by Marc Balmer, CH-4055 Basel, Switzerland.
Internet applications written in the Java programming language are mostly designed as applets that run in a Java enabled browser like Netscape.
There are, however, still many web-browser around that don't support Java. These need to use CGI (Common Gateway Interface) to access interactive pages on the web. Although CGI programs traditionally were realized using a scripting language like Perl or even the Bourne shell, nothing speaks against using Java to write CGI program.
