Older blog entries for mathrick (starting at number 39)

Had the strangest bug today.

During Computer Architecture labs we were supposed to write utterly trivial distributed app using PVM (Parallel Virtual Machine or something) libs. And so we did. All was nice and dandy, app would spawn worker processes, send them data (that is, 3 integers) which would then get summed and sent back to master process. Everything was cool, working set was split into correct number of messages, each was sent correctly, replies sent back, except that the very last one just wasn't making it. It would simply disappear into oblivion, leaving parent process hanging there ad infinitum.

Obviously we debugged it, added some control printf()s (debugging distributed app on remote site with no gdb installed isn't nice in general, but this one was hopefully trivial enough to only need couple of printf()s here and there), corrected few obvious mistakes and, umm, nothing. It would just hang there. So we got LA (Laboratory Assistant) to take a look at it if we didn’t make any stupid mistake in PVM code. Nope. All clear and correct. We tried fiddling with size of data and number of child process – now it ran to the end and exited cleanly, but results were clearly bogus. Change back to old settings – hang.

So, we analysed it over and over, checked the algo several times, nothing. During random bashing of debug printf()s, I moved one few lines down in the code to get it to print slightly different set of data, and then – *poof*, it just worked. I moved exactly 1 (one) printf(). It changed no control flow. But suddenly, the app just worked. When I got the printf() back into old position, it still worked. The untraceable bug just disappeared, appropriately, without trace.

Update: So advogato doesn't allow <acronym></acronym>. Grrr

SamBakZa strikes again! In case you haven’t seen first part of “There she is!” yet, you can see it here as well.

So, browsing the web I’ve come by this screenshot with extremely fine piece of art in it. Now I have it on my desktop too, but there’s a problem: I know literally nothing about the image, author or source of it. So if you can recognize anything about the image, please drop me a line (you can do that via comment form, for majority of you who read it via some syndication :). I’ll be very grateful for anything that would help me identify the drawing somehow.

Just finished Prince of Persia: Sands of Time. Very addiciting game, has drawn me away from doing more productive things :\\. Really, the evolutions that guy does are totally incredible, make Matrix look like bunch of acrophobia-ridden weenies. The only weakness is that it’s short (13h total) and after you end it, it’s closed – nothing left to be done, you’ve seen everything. Oh, and also camera sometimes tends to be high on crack, which is annoying. But gameplay makes you forget about insignificant details like that ;). Graphics are very nice, a “bit” of progress since original PoP, but it’s addicting just like back then.

On unrelated note, comments spam is becoming very annoying. I can stand a lot, but aggressive porn spam is just a bit too much. Dunno, maybe I should disable comments entirely? But I like when people have comments on their sites, so I want to have them in my blog too. Definitely should look for some spam-assassin for WordPress, anyone has good recommendations for that to spare me some unnecessary R&D hours? If so, drop me a note (yes, you can use comments for that ;)

Just finished Prince of Persia: Sands of Time. Very addiciting game, has drawn me away from doing more productive things :\. Really, the evolutions that guy does are totally incredible, make Matrix look like bunch of acrophobia-ridden weenies. The only weakness is that it’s short (13h total) and after you end it, it’s closed – nothing left to be done, you’ve seen everything. Oh, and also camera sometimes tends to be high on crack, which is annoying. But gameplay makes you forget about insignificant details like that ;). Graphics are very nice, a “bit” of progress since original PoP, but it’s addicting just like back then.

On unrelated note, comments spam is becoming very annoying. I can stand a lot, but aggressive porn spam is just a bit too much. Dunno, maybe I should disable comments entirely? But I like when people have comments on their sites, so I want to have them in my blog too. Definitely should look for some spam-assassin for WordPress, anyone has good recommendations for that to spare me some unnecessary R&D hours? If so, drop me a note (yes, you can use comments for that ;)

Just finished Prince of Persia: Sands of Time. Very addiciting game, has drawn me away from doing more productive things :\. Really, the evolutions that guy does are totally incredible, make Matrix look like bunch of acrophobia-ridden weenies. The only weakness is that it’s short (13h total) and after you end it, it’s closed – nothing left to be done, you’ve seen everything. Oh, and also camera sometimes tends to be high on crack, which is annoying. But gameplay makes you forget about insignificant details like that ;). Graphics are very nice, a “bit” of progress since original PoP, but it’s addicting just like back then.

On unrelated note, comments spam is becoming very annoying. I can stand a lot, but aggressive porn spam is just a bit too much. Dunno, maybe I should disable comments entirely? But I like when people have comments on their sites, so I want to have them in my blog too. Definitely should look for some spam-assassin for WordPress, anyone has good recommendations for that to spare me some unnecessary R&D hours? If so, drop me a note (yes, you can use comments for that ;)

As it turns out, “OOo_1.9.m65_native_LinuxIntel_install” is in fact collection of RPMs stuffed into .tgz (!?). Great installer indeed. How cool that 1) I have Debian 2) I don’t want to install it systemwide but only have a quick peek. Yay for great installers!

Released Libmms 0.1 earlier today, finally. This is also my first release ever, quite a bit of knowledge to swallow. Following the release, gst-mms also got commited to GStreamer CVS repo. Still has some issues, I have my suspicions, we will see.

This is very good timing, btw, as today is my birthday. The feeling that you’re able to contribute something useful back to community is the greatest gift I could get. Also, got boxed copy of Fallout to replace for lost CD of one I bought long ago (too bad it’s PL version, not EN, but oh well), and new mouse to replace my beloved A4Tech SWW-5 NetEasy 3D Mouse, which recently started showing signs of age. New mouse if from Media-tech this time, and is called “Web Master 4d Mouse", although my bro (who has his birthday tomorrow :) immediately renamed it to “Darkness Master” as it’s black and pretty bad-ass looking :). What I like about it is symmetry, making is suitable for both left- and right-handed part of population. Of course it has 3rd button under thumb (that’s very basic requirement for any mouse I’m supposed to even touch), mirrored on the other side, totalling to 5 buttons (left, right, left thumb, right thumb, and under the wheel). Gotta see if I can program this wealth of buttons to do something useful under X. Oh, and it’s old-fashioned, non-cordless, non-optical mouse, just as God intended. Yay!

So, looks like I’ll have to spend some of my precious time killing certain Rich, for he attempted to spoil my fun of reading Prattchet’s book when it comes out in PL. I mean, it’s very good to advertise Prattchet to anyone who may not know his works yet, but for heavens sake, DON’T just go all happy, let’s-put-some-spoilers all of sudden. It’s already hard enough to avoid accidentally reading these highly annoying synopses publishers just love to put on the backcovers. If I also have to defend myself from fellow men, that’s going to lower my chances of retaining some kind of mental stability significantly. Now, you don’t want to be driving a geek insane, do you?

wingo, “I see no beastly problem here". Instead, I see area filled with several, resonably well defined problems, each of reasonable size and complexity. Think Unix, dude (hint: CORBA isn’t Unix, CORBA thinking isn’t Unix thinking)