ubuntu: sem_timedwait not waking (C)

Question

I have 3 processes which need to be synchronized. Process one does something then wakes process two and sleeps, which does something then wakes process three and sleeps, which d

Answer 1

I gave the program a shot on my Ubuntu 10.04 x86_64 Core i7 machine.

When running with usleep(40000), the program ran fine for half an hour or something boring.

When running with usleep(40), the program ran fine for another half hour, maybe more, before my machine froze. X died. Control+alt+F1-7 died. I couldn't ssh in. (Sadly, this goofy Apple keyboard doesn't have a sysrq key. I like typing on it, but I sure don't need f13, f14, or f15. I'd do horrible things to get a proper sysrq key.)

And the absolute best: NOTHING in my logs tells me what happened.

$ uname -a
Linux haig 2.6.32-22-generic #36-Ubuntu SMP Thu Jun 3 19:31:57 UTC 2010 x86_64 GNU/Linux

At the same time, I was also playing a Java game in browser (posted by a fellow stackoverflow user looking for feedback, fun diversion :) -- so it's possible that the jvm is responsible for tickling something to freeze my machine solid.