Shell Programming and Scripting

Hi I am having a problem exiting a WHILE loop. I am on a Sun server using ksh.

I am running a Veritas Cluster Software (High Availablity) command to obtain a group status and grepping the command output for status "G" which means that the filesystem is frozen and therefore not available to failover. When the status is no longer "G" then the group is free to failover and the loop should exit with the message "group1 is now ONLINE". However when the condition is met the loop does NOT exit and continues looping.

Code as follows:

Code:

#!/bin/ksh
 
#echo ""
#echo ""
#      while true
#                 do
#                  /opt/VRTSvcs/bin/hastatus -sum | grep "G  group1"
#                   sleep 15
#                 done
#echo ""
#echo ""
#echo ""
#echo "group1 is now ONLINE"

Can anyone help me here?

Replace

Code:

while true
do
/opt/VRTSvcs/bin/hastatus -sum | grep "G group1"
sleep 15
done

with

Code:

while /opt/VRTSvcs/bin/hastatus -sum | grep -q "G group1" 2>/dev/null
do
sleep 15
done

Why should the loop exit; true is true and will always stay true. Why don't you use grep's exit code which is 0 if pattern found and 1 if not? Sth. like

Code:

while /opt/VRTSvcs/bin/hastatus -sum | grep "G  group1"

?

guys - thank you both very much for your prompt replies! Works fine now.