#!/bin/bash
##########################################################################
# Shellscript: timeout - set timeout for a command
# Author : Heiner Steven <heiner.steven@odn.de>
# Date : 29.07.1999
# Category : File Utilities
# Requires :
# SCCS-Id. : @(#) timeout 1.3 03/03/18
##########################################################################
# Description
# o Runs a command, and terminates it (by sending a signal) after
# a specified time period
# o This command first starts itself as a "watchdog" process in the
# background, and then runs the specified command.
# If the command did not terminate after the specified
# number of seconds, the "watchdog" process will terminate
# the command by sending a signal.
#
# Notes
# o Uses the internal command line argument "-p" to specify the
# PID of the process to terminate after the timeout to the
# "watchdog" process.
# o The "watchdog" process is invoked by the name "$0", so
# "$0" must be a valid path to the script.
# o If this script runs in the environment of the login shell
# (i.e. it was invoked using ". timeout command...") it will
# terminate the login session.
##########################################################################
PN=`basename "$0"` # Program name
VER='1.3'
TIMEOUT=5 # Default [seconds]
Usage () {
echo >&2 "$PN - set timeout for a command, $VER
usage: $PN [-t timeout] command [argument ...]
-t: timeout (in seconds, default is $TIMEOUT)"
exit 1
}
Msg () {
for MsgLine
do echo "$PN: $MsgLine" >&2
done
}
Fatal () { Msg "$@"; exit 1; }
while [ $# -gt 0 ]
do
case "$1" in
-p) ParentPID=$2; shift;; # Used internally!
-t) Timeout="$2"; shift;;
--) shift; break;;
-h) Usage;;
-*) Usage;;
*) break;; # First file name
esac
shift
done
: ${Timeout:=$TIMEOUT} # Set default [seconds]
if [ -z "$ParentPID" ]
then
# This is the first invokation of this script.
# Start "watchdog" process, and then run the command.
[ $# -lt 1 ] && Fatal "please specify a command to execute"
"$0" -p $$ -t $Timeout & # Start watchdog
#echo >&2 "DEBUG: process id is $$"
exec "$@" # Run command
exit 2 # NOT REACHED
else
# We run in "watchdog" mode, $ParentPID contains the PID
# of the process we should terminate after $Timeout seconds.
[ $# -ne 0 ] && Fatal "please do not use -p option interactively"
#echo >&2 "DEBUG: $$: parent PID to terminate is $ParentPID"
exec >/dev/null 0<&1 2>&1 # Suppress error messages
sleep $Timeout
kill $ParentPID && # Give process time to terminate
(sleep 2; kill -1 $ParentPID) &&
(sleep 2; kill -9 $ParentPID)
exit 0
fi
