[PLUG] spawning

[MaD dUCK <madduck@madduck.net>]

another question to the list(s), just because you guys provide answers
fast and i am learning...

- when i start xterm& from another xterm window, the new xterm window
  survives when the parent xterm window is closed.

- when i start something like xscreensaver& from .xsession (or
  ssh-agent), it does not terminate when .xsession terminates.

from all this i am led to believe that spawning a process with the &
operator (?) detaches it from the parent process, so that killing the
parent does not affect the spawned child. however, then i do this from
an xterm:

madduck@fishbowl ~> ps
  PID TTY          TIME CMD
  523 pts/16   00:00:00 bash2
 2484 pts/16   00:00:00 ps
madduck@fishbowl ~> xterm&
  [1] 2503
madduck@fishbowl ~> ps
  PID TTY          TIME CMD
  523 pts/16   00:00:00 bash2
 2503 pts/16   00:00:00 xterm
 2559 pts/16   00:00:00 ps
madduck@fishbowl ~> ps -fC xterm
UID        PID  PPID  C STIME TTY          TIME CMD
madduck   2503   523  0 22:50 pts/16   00:00:00 xterm

and find that xterm is still parented by the bash shell that spawns
it. when i close that bash shell, the parent id becomes 1.

i look further at windowmaker:

- when i start xterm& from windowmaker and close windowmaker (which is
  at the end of .xsession), techically, windowmaker should terminate
  along with its children, but leave the x server open with the xterm.
  but it doesn't... closing windowmaker terminates the xterm& window
  as well.

and mutt/urlview/netscape:
  
- when i have mutt spawn netscape to display a url via urlview
  (default config) and then close mutt, netscape is killed.

and i am left a little clueless.

just how does spawning and process parenting work then? the reason i
am asking is because everytime i log out of my x server, my ssh-agent
session continues to live, so after a couple of days i have some 15
ssh-agents running, and that's annoying... up to know i was expecting
them to die when .xsession dies as a result of wmaker (it's last
line) exiting... can this be enabled? how would one go about making
sure that ssh-agent does not survive after it is not used anymore? a
'kill' after wmaker?

thanks,
martin

[greetings from the heart of the sun]# echo madduck@!#:1:s@\@@@.net
-- 
you work very hard. don't try to think as well.


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