topic Re: nohup problem in Operating System - HP-UX

nohup problem

Gary L. Paveza, Jr. — Fri, 22 Oct 2004 13:49:26 GMT

I'm trying to capture the PID of a process started via nohup. According to the man page for nohup, I should be able to do the following:

nohup (command1; command2)

However, when I try the following:

nohup (sleep 10; echo $!) &

I get the following error:

ksh: syntax error: '(' unexpected

Anyone know how I can get the PID for the first command?

Re: nohup problem

Steven E. Protter — Fri, 22 Oct 2004 13:52:26 GMT

PID=$$

echo "Process ID: $PID:

Try command witout the parenthesis.

sEP

Re: nohup problem

Gary L. Paveza, Jr. — Fri, 22 Oct 2004 13:56:16 GMT

without the parens it only nohups the first command, then executes the second. The variable $! returns the PID of the nohup command. I need the PID of the command started by nohup.

Re: nohup problem

Ken Penland_1 — Fri, 22 Oct 2004 13:57:13 GMT

how bout this:

nohup `sleep 10; echo $!` &

Re: nohup problem

Uday_S_Ankolekar — Fri, 22 Oct 2004 14:01:13 GMT

Try without brackets

nohup sleep; echo $!) &

USA..

Re: nohup problem

Ken Penland_1 — Fri, 22 Oct 2004 14:02:18 GMT

naw, I see what his problem is, the echo $! returns the pid of the nohup, and not the sleep...hrm....I cant figure it out either.

Re: nohup problem

Uday_S_Ankolekar — Fri, 22 Oct 2004 14:09:14 GMT

Ignore my previous post!

Try this instead:

nohup `(sleep 10; echo $!)` &

Re: nohup problem

Geoff Wild — Fri, 22 Oct 2004 14:14:12 GMT

nohup `(sleep 10; echo $!)` &

That won't work - as ; seperates cmmands - serially - that is, nohup will do first command, after done, the second...

Only way I see is:

nohup command &
ps -ef |grep command |awk '{print $2}`

Rgds...Geoff

Re: nohup problem

Ken Penland_1 — Fri, 22 Oct 2004 14:22:40 GMT

why do you need to nohup it?

just typing:

sleep 10 &

then echo $! returns the correct number... when ya start including nohup it starts getting messy cause THAT is considered the last job that ran in the background

Re: nohup problem

Tom Danzig — Fri, 22 Oct 2004 14:24:32 GMT

If all you want is the pid of the nohup'ed process, it is stored in $!

i.e.

# nohup sleep 60 &
[1] 11187
# Sending output to nohup.out

# echo $!
11187

Re: nohup problem

Ken Penland_1 — Fri, 22 Oct 2004 14:27:00 GMT

thats not what he wants Tom, that gives you the pid of the nohup, not the pid of the SLEEP

Re: nohup problem

Geoff Wild — Fri, 22 Oct 2004 14:30:42 GMT

actually, it does:

sha1:root:/ # nohup sleep 20 &
[1] 19692
sha1:root:/ # Sending output to nohup.out

sha1:root:/ # echo $!
19692
sha1:root:/ # ps -ef |grep 19692
root 19692 23610 0 13:30:13 pts/8 00:00 sleep 20

Rgds...Geoff

Re: nohup problem

Gary L. Paveza, Jr. — Fri, 22 Oct 2004 14:46:23 GMT

Geoff,

That's exactly what I need. Thanks.

Re: nohup problem

Gary L. Paveza, Jr. — Fri, 22 Oct 2004 14:55:57 GMT

Tom provided the solution and Geoff confirmed it.