On Aug 3, 2007, at 9:00 AM, T&B wrote:

> Hi Jeff,
>
>>> 2. How can I unmount the external Backup drive when the script is  
>>> done, so it can be safely unpugged (FireWire)?
>
>> /usr/sbin/diskutil eject '/Volumes/The DriveName'
>
> That seems to work great, thanks :-)
>
> Now I just need an answer to:
>
>>> 1. How can I check whether the external volume "Backup" is  
>>> mounted, and conditionally execute the script (else mail to say  
>>> there was an error). Simply checking whether /Volumes/Backup  
>>> exists isn't reliable since there may be a directory created  
>>> there (as I've seen created when the script runs with no disk  
>>> attached).

Hi tom

are you writing this just in shell or using applescript also?

here is an apple script check.

tell application "Finder"
	display dialog ¬
		"What volume name?" with icon 1 default answer " "
	set UID to (text returned of result)
	
	activate
	if exists disk UID then
		display dialog UID & " is already mounted " with icon 0
	else
		display dialog " some unix mount code goes here "
		
	end if
end tell

here is a bash script check; -- i haven't tried this on in a while.  
Basically you grep an " ls " for the volume name you want.

#!/bin/bash
if [ -z $1 ] ; then
     echo "usage : disk <jdonovan>"
     echo "Mounts <jdonovan> if it's not mounted, and"
     echo "unmounts it if it is already mounted."
     exit 1
fi
NAME=$1
PART=`diskutil list|grep $NAME|awk '{print $6}'`

if [ -z `ls -1 /Volumes/ | grep $NAME` ] ; then
     # check that PART appears to be a disk partition
     echo Checking $NAME $PART
     if [ `file /dev/$PART | awk '{print $2}'` = "block" ] ; then
   echo Mounting $NAME $PART
      diskutil mount /dev/$PART
     else
        echo /dev/$PART does not appear to be a disk partition - exiting
   exit 1
     fi
else
     echo unmounting $NAME
     diskutil unmount /Volumes/$NAME
fi