Darrin Chandler <[EMAIL PROTECTED]> wrote:
If you really want to find the parent you can...
$ ps ax -O pgid | grep ntpd
4887 4887 ?? Is 0:00.01 ntpd: [priv] (ntpd)
7164 4887 ?? I 0:00.06 ntpd: ntp engine (ntpd)
The header that gets stripped by grep:
PID PGID TT STAT TIME COMMAND
So you can see that for one process PID==PGID. Bingo.
Yes, but there might be a race condition while checking.
What I would like to do is to check if a shell script is already active. And
I don't want to use a lock file:
if [ $(pgrep -of "/bin/sh $0") -ne $MYPID ]; then
echo "I'm already active:" 1>&2
echo $(pgrep -olf "/bin/sh $0") 1>&2
exit 1
fi
If pgrep (with -o support) finds a process that is *older* than MYPID the
script is already active.
afaik that construction is faster than grepping ps, piping and comparing two
values but if there is a better solution I'm pleased to hear about. :)
--
No Swen today, my love has gone away
My mailbox stands for lorn, a symbol of the dawn
