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Commands using wait

Commands using wait from sorted by
Terminal - Commands using wait - 5 results
sh time.sh 1 20 & var1="$!" & sh time.sh 2 10 & var2="$!" & sh time.sh 3 40 & var3="$!" & sh time.sh 4 30 & var4="$!" ; wait $var1 && wait $var2 && wait $var3 && wait $var4
2012-03-31 10:03:58
User: julnegre
Functions: sh wait
Tags: PID wait asynchronous $!
0
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Asynchronous PID Management

This command explains how to manage some asynchronous PID in a global process.

The command uses 4 processes in a global process. The asynchronous scripts are simulated by a time.sh script

more infos :

http://code-esperluette.blogspot.fr/2012/03/bash-gestion-de-processus-asynchrones.html

http://www.youtube.com/watch?v=TxsPyAtD70I

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(sp-sc sop://broker.sopcast.com:3912/80562 8908 10999 &>/dev/null &); sleep 10; wait $(vlc http://localhost:10999); killall sp-sc
2011-04-06 00:08:38
User: Bonster
Functions: killall sleep wait
Tags: mplayer sopcast sp-sc
0
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View a sopcast stream

requires sp-auth installed

This command will auto kill sp-sc after vlc is closed, so u wont have to do it manually

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wait $!
2010-06-07 21:56:36
User: noahspurrier
Functions: wait
Tags: automation while process ps wait halt
2
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Wait for an already launched program to stop before starting a new command.

Referring to the original post, if you are using $! then that means the process is a child of the current shell, so you can just use `wait $!`. If you are trying to wait for a process created outside of the current shell, then the loop on `kill -0 $PID` is good; although, you can't get the exit status of the process.

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$COMMAND 2>&1 >/dev/null & WPID=$!; sleep $TIMEOUT && kill $! & KPID=$!; wait $WPID
2010-05-26 11:12:26
User: keymon
Functions: kill sleep wait
3
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Execute a command with a timeout

I like much more the perl solution, but without using perl. It launches a backgroup process that will kill the command if it lasts too much.

A bigger function:

check_with_timeout() {

[ "$DEBUG" ] && set -x

COMMAND=$1

TIMEOUT=$2

RET=0

# Launch command in backgroup

[ ! "$DEBUG" ] && exec 6>&2 # Link file descriptor #6 with stderr.

[ ! "$DEBUG" ] && exec 2> /dev/null # Send stderr to null (avoid the Terminated messages)

$COMMAND 2>&1 >/dev/null &

COMMAND_PID=$!

[ "$DEBUG" ] && echo "Background command pid $COMMAND_PID, parent pid $$"

# Timer that will kill the command if timesout

sleep $TIMEOUT && ps -p $COMMAND_PID -o pid,ppid |grep $$ | awk '{print $1}' | xargs kill &

KILLER_PID=$!

[ "$DEBUG" ] && echo "Killer command pid $KILLER_PID, parent pid $$"

wait $COMMAND_PID

RET=$?

# Kill the killer timer

[ "$DEBUG" ] && ps -e -o pid,ppid |grep $KILLER_PID | awk '{print $1}' | xargs echo "Killing processes: "

ps -e -o pid,ppid |grep -v PID | grep $KILLER_PID | awk '{print $1}' | xargs kill

wait

sleep 1

[ ! "$DEBUG" ] && exec 2>&6 6>&- # Restore stderr and close file descriptor #6.

return $RET

}

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wait
2010-01-15 04:03:11
User: bhepple
Functions: wait
Tags: automation while process ps wait halt
0
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Wait for an already launched program to stop before starting a new command.

If you really _must_ use a loop, this is better than parsing the output of 'ps':

PID=$! ;while kill -0 $PID &>/dev/null; do sleep 1; done

kill -0 $PID returns 0 if the process still exists; otherwise 1

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