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1

I need to find out if a variable contains a certain text string, then do something about it.

Here is what I mean, but I don't know how to get a "contains" operator


# We have volumes called:
#  /Volumes/BackupsA_K
#  /Volumes/BackupsL_Z
#  /Volumes/Backups_Admin
# (could be more, etc)

# Any of these volumes could be mounted, and we want to unmount it if it exists.

# We'll see if any volumes containing "Backups" is in /Volumes/
theVolume=`(ls /Volumes | grep "Backups")`

# Just to see that we're getting a full volume name
echo $theVolume
## Let's say $theVolume is Backups_Admin

if [ $theVolume CONTAINS "Backups" ]; then
         unmount /Volumes/$theVolume
         else
         echo "No Backup Volumes Mounted"
fi

# so we need to see if $theVolume contains the word "Backups".

Thanks!!

2 
if [[ `expr ${theVolume} : 'Backups'` -ne 0 ]]; then
   echo 'found'
else
   echo 'not found'
fi;
3

That doesn't seem to work. It's doing the "else", even though Backups_Admin is in /Volumes/

4

sorry 'bout that:

#!/bin/sh

theVolume='/foo/Backups'
#theVolume='/foo/Backup'

if [ `expr "${theVolume}" : '.*Backups.*'` -ne 0 ]; then
  echo 'found'
else
  echo 'not found'
fi;

or without using the external 'expr' - under ksh:

#!/bin/ksh

theVolume='/foo/Backups'
#theVolume='/foo/Backup'

if [[ "${theVolume}" = @(*Backups*) ]]; then
  echo 'found'
else
  echo 'not found'
fi;
5

Yeah, I don't think this is going to work. I'm os OS X and I don't have the korn shell on the client computers.

I'll figure out a way. I think all I need is the unmount command, because if the directory isn't there, then it won't really matter that unmount returns an error (logout script).

Oh well, thanks anyway!!

6

the first solution is NOT really a ksh solution - it will work under Bourne. I've just changed the '#!/bin/ksh' to '#!/bin/sh' - it's been a habit of mine to write everything under ksh....