SIGUnix

Minutes for 2000.09.28

Project Updates

NJAMD

NJAMD is now in the RedHat distribution.

LimitGuard

Studied how to use CVS.

Bugfixes

Now meeting right after SIGUnix meetings.
How does one pre-emptively detect if one can or cannot rename a file?

pftp

Didn't meet last week; Lars out of town.

MP3-Player

defunct?

General Discussion

New package formats

HPML?
RPM 4 breaks stuff
Need abstractions in package management
RPM and Debian have different design goals
Defaults are hard to determine
Should one start up apps after installation? Security vs. Ease
Automatic alternatives? E.g., xterminal could start xterm or rxvt.
Separate packages from installation policy
Have separate policy for each architecture

Parts prices

HD prices are now down to $3/GB.
RAM has levelled off.
RAMBUS is evil.

Meeting mini-presentation: Job control

Basic process life cycles

^Z: suspend a process
bg: resume a suspended process in the background
fg: put a suspended process into the foreground

Multiple suspended jobs

jobs: list background or suspended processes, along with a job number
%n: shell expands to PID of job n. Useful for kill %1, to kill the recently-suspended process.

Common signals

HUP: reset
TERM: exit
KILL: uncatchable kill
USER1: program-specific usefulness
INT: same as ^C
SEGV: force a coredump
STOP: suspend; like ^Z

Killing information

kill -1 kills all processes possible.
killall on Linux and BSD kills processes by name; on others, kills all processes

Control characters

^S: put lock on stdout
^Q: release lock put on by ^S
^O: no more output to the terminal, keep running
^\: send SEGV signal
^D: EOF; exit shell; end input; tab-completion filename expansions; delete character if in the middle of line
^V: send the next character sequence literally