Minutes for 2000.10.05

Go to the ACM conference this weekend!

Project Updates

Note: some projects may be missing from the update list because the secretary arrived late.

pftp

Met on Sundary
coded some

LimitGuard

didn't meet, and probably not next weekend, due to conference

MP3-Player

declared defunct by its coordinator
has anything been done with VQF, a new audio format?
alledgedly, VQF is 30% smaller than mp3, and has a better high/low range

Distribution

Met
Downloaded some stuff
There are lots of RedHat CD's in the office

General Discussion

Member has Linux kernel panics

Using kernel 2.2.17
suspects Hardware; are there any tools available to analyze hardware?

Member is rooted

During running, found top and any other command segfaulted
Found strange kernel module being loaded, with recent timestamp

Using GL full-screen apps

Apparently, don't use two full-screen GL apps at once
For example, Quake and GL screensavers can cause a machine to lock

Meeting mini-presentation: Fork/exec

fork(): creates a copy of the currently-runnining process; generally used in combination with exec(); found in C and Perl
exec(command): replaces the current process with command; used with fork(), is the method to create new processes
clone() on Linux: similar to fork, but user can decide what is shared between the child and parent; useful for threading

Forking processes creates a process tree.

`ps`

ps is used to view process information.

arguments/options

elf: popular on on SysV for display most useful information; supported on some BSD's
aux: on BSD, similar to elf

General Process Information

root of process tree, init

The root of the process tree is init, which has a PID of 1. Killing init has the effect of killing the system.

Killing parents, children

In general, killing the parent of a process kills all descendants.

When a child exits, the parent must wait() to clean up after it. Until the parent performs this wait, the child is a zombie. If the parent doesn't wait, and exits, the clean-up is delegated to init, which will then clean-up the child, eliminating it as a zombie.