Shell Programming and Scripting

Hey Alister,

Yes I WAS lucky to get that desired ouput. After a while, I found out am unlucky.. It again started creating that mess. Also the problem is my system doesn't contain pgrep I found out another way to accomplish my result.

If there is any other way that we can acquire the result with grep, wc or other silly commands, please post here..

Exactly which version of which operating system you are using?

It will help to know exactly what you're trying to accomplish. Show us the shell script and explain what it's supposed to do.

Regards,
Alister

Hint:

Code:

ps -ef >tmpfile
count=$(grep $0 tmpfile |grep -v grep |wc -l)
...

--
Bye

EDIT: LOL, obviously in this case there's no need to purge "grep" strings from grep output.

@Lem: you are simply awesome.

@Alister: I have a cron which runs my script every 1 minute. If any error identified by my script, it runs another program which takes a while say 4 mins. Until it gets completed, my Cron should not allow the Script to run on the next minute.. So i thought of counting the number of PS of that script name will fix that problem. Thanks to Lem for that Solution.

What I have built is as below:

Code:

pd=$(head -1 pid.check)
ps -ef | grep $pd | grep -v grep 
if [ $? -eq 0 ]; then
exit 0
fi

pid1=$$
echo "$pid1" > pid.check

Shout me if the above fails at any condition, I will correct my code. Thanks

Needs a "first time" condition. Also, if you know the pid just look for the one pid. You can dump the output from ps as you only need to know if the process is still running.

Code:

# Has previous script finished?
if [ -f pid.check ]
then
       pd=$(head -1 pid.check)
       ps -fp $pd 1>/dev/null
       if [ $? -eq 0 ]
       then
              exit 0
       fi
fi
# Record pid of current script
pid1=$$
echo "$pid1" > pid.check
### PROCESSING GOES HERE

It would be better to specify a directory (e.g. /var/tmp) for pid.check file or it will be created in the home directory of the owner of the crontab.