Differences between running in the foreground and the background 1

[columb]

I have a script which looks like

#!/bin/ksh
 
dt_lin()
 {
 echo $(date +%y%m%d_%H:%M) : $1 >> /home/b40217/testloop.log
 }
 
while [ 1 ]
do
  if ssh testbox "ls /tmp/col050201 >/dev/null 2>&1"
  then
    dt_lin "Found it"
    exit 
  else
    dt_lin "looking"
  fi
  sleep 10
done

If I run this a a foreground process all is well and it duely logs that it is looking every 10 seconds. However I want to run this as a background process so I'm running

nohup ./testloop &

and after an initial entry there's nothing written to the log or nohup.out. I've checked and ps shows the loop as running. Can anyone explain this please?

Columb Healy

 

[PHV]

What is the behaviour of ssh in background ?
You may try any combination of -f -n and -t options for ssh.

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ222-2244

 

[columb]

PHV

Once again you come up trumps!
Many thanks.

Columb Healy

 

[columb]

Maybe I should have said for others who may read this post the -n option solved it.

Columb Healy