vnode.ch virtual home of a Unix developer

Most toolkits for graphical user interfaces organize the elements of the user interface, typically called "widgets", in a hierarchy: Starting with some container like a dialog or window at the top, the elements like push buttons, labels, or layout managers are added. To add new elements a set of C functions is provided which are called with a handle to the parent widget, the class (or type) of widget that is to be added plus any further arguments like e.g. a label string in the case of a push button.

While it is relatively easy to expose the widget creation and managing functions to Lua, the resulting Lua program will still closely resemble the same functionality coded in C. So the aim is to use Lua's table constructors to define a GUI instead of calling the widget creation routines.

I reworked the GPIO framework in OpenBSD last fall. Now I have taken my work to NetBSD and updated their GPIO implementation. While there, I corrected some mistakes made in the OpenBSD implementation and took it a step further. More development will take place in NetBSD, and there is quite a few interesting upcoming things to watch out for...

If you are interested in the latest userland accessible GPIO stuff, and the most up-to-date GPIO implementation, then keep an eye on NetBSD -current. This is where I am working on new stuff.

See http://blog.netbsd.org/tnf/entry/gpio_revisited for details. And stay tuned.

The other day, I got an email from Edd, an OpenBSD user, claiming that Samba would crash when serving files off an MS-DOS filesystem. This was Samba built from sources and not the one from ports. Since I use myself Samba a lot and for a quite large user base, I got interested in the issue and started investigating it.

What I found out in the end is a surprise and was not expected: A bug that has been there in all BSDs for almost all the time, since the 4.2BSD times or for roughly 25 years...

A while ago, Maurice Janssen (maurice@z74.net) sent me a modification of the nmea(4) line discipline to support the Meinberg Standard Time String format. With only a few changes, nmea(4) was turned into the msts(4) line discipline to support Meinberg's serial data format that can be emitted by all their radio clocks. I modified the code a bit, added a manual page, and added the bits needed to attach msts(4) to a tty to the ldattach(8) command. The result is that OpenBSD now has support for virtually any Meinberg radio-clock ever built.

I am currently writing a control and monitoring software system that makes use of GPIO pins. Since I was at the CCC congress in Berlin I did only have my laptop and no real GPIO hardware...

With only a laptop it's a bit hard to write GPIO software, since laptops usually don't have any GPIO pins. So what I needed to test my new software was either a real device (out of reach) or... writing a simulator.

All of these projects, except dynload and mod_clamscan, are in the OpenBSD ports and packages collection.

• smtp-vilter, a fast and flexible content filter for sendmail
• smtp-benchmark, an SMTP benchmark programs
• ldapvacation, an LDAP version of the vacation program