Handling failed mount (media not connected)

[Garrett Cooper]

Robert Huff wrote:
> L Goodwin writes:
>
>   
>>  My backup script (sh) works fine except when the
>>  backup drive (USB Flash drive) is not plugged in. I'm
>>  using mount_msdosfs to mount the backup drive.
>>  
>>  What is the best way to handle mount_msdosfs error?
>>  If the drive is not mounted, I want to detect the
>>  failure and execute error-handling code.
>>     
>
> 	First approximation, using sh:
>
> 	ls /dev | grep da4s1
> 	if [ $? -eq 0 ];
> 		then
> #	drive is available
>
> 		else
> #	drive is not available
>
> 	if
>
> 	(Replace "da4s1" with whatever the flash drive gets created
> as.)
>
>
> 				Robert Huff
>   

    Possibly better (using sh again..):

#!/bin/sh

error_handling_func() {
    err_code=$1; shift;
    # do something here...
    exit $err_code;
}

# This assumes that you have:
#    1. cam/pass support built into the kernel.
#    2. your USB device is interpreted as a SCSI device (which should be 
the case).
#    3. your USB device is unique / identifiable by a string.
camcontrol | grep 'Device string' || error_handling_func $?

# do something here since it passed..

    Also, FWIW conditionals are actually done like:

if {statement} ; then

elif {statement}; then

else

fi

    in Bourne shells.

    Also, mount_msdosfs should return a non-zero exit code.

Cheers,
-Garrett