Shell Programming and Scripting

The below code is still returning zero when you have 6 processes running

Code:

ps -ef|grep "sqlplus -s"|grep -v grep|wc -l

You can see that the number of jobs goes to [6] in the output, you then get the error about cnt=0 and then in jumps to [12].

My code was doing the correct thing to start with. It started 6 jobs and was was waiting for one of them to finish. You did ps -ef | grep "sqlplus -s" and didn't see anything so you assumed no jobs were started. The issue was that the processes aren't being picked up by the grep search.

As I suggested before start a job and then do ps -fp <pid> to find out what the command line is, this will help debug why grep "sqlplus -s" is not matching it.


The test on numeric value should have || this is "or" in shell not "pipe".

Oh ok, got it about || ... forgot about it ...

For me "ps -ef|grep "sqlplus -s"|grep -v grep|wc -l" is showing the number of sessions running correctly. It shows 6 processes or less when the script is running. Not sure why you are getting 0.

Your code with "jobs" and "wait" just didn't go beyond the first 6 sqls for me. This whole job involving 50 tables takes only 2 minutes but when running your code it processed only 6 sqls and just didn't move further even after 5 minutes. I had to kill (ctrl+C) it everytime. I just tried it again and it gives the same results, only 6 sqls are processed and 6 logfiles are generated.

If you feel like debugging it just run jobs with output to the terminal before the sleep:

Code:

#!/bin/ksh
PROCS=6
SLEEP=20
while read LINE
do
     while true
     do
         NUM=$(jobs | wc -l)
         echo NUM=$NUM
         if [ $NUM -lt $PROCS ]
         then
             stuff "$LINE" &
             break
         else
             jobs
             echo "========"
             sleep $SLEEP
         fi
    done
done < textfile
# wait for ALL remaining processes
wait

It works fine if I run the sleep command as my background task, but I'm curious about what in your environment is causing jobs to still keep reporting stuff thats finished.

Yeah Chubler, something in our envirorment does behave weird. If I replace "ps -ef" with "jobs" it just doesn't go beyond the first 6 sqls. Anyways, "ps -ef" works fine for me, occasional bad number error is there, when the "ps -ef" count is 0.

Thanks a great lot