Is there a way to get a pendrive to use the same drive name each time it
is inserted ?

When I insert one into the same port, I get sdd1 or sdc1.

Yes and no.

No in the sense that you can't control the letter that is assigned to the block device (Ex: /dev/sdb vs /dev/sdc)

There are however other options. You can symlink sdd or sdc (whichever the pendrive takes on) to a known value everytime it's inserted by using udev rules on your device. You could insert your pendrive and know that it is symlinked, for example, to /dev/mapper/my_drive1 for mounting. You can find an article on by searching for 'udev symlinks', I found one here.

Other options include labeling (by using e2label for example, but that's specifically for ext based filesystems, and may not be what your wanting. While it will control how your pen drive appears within the desktop environment, it won't change the block device name for mounting.

You can give it a 'label' or use the UUID in your /etc/fstab file to give it a specific mount point.

you can add label to the partitions, filesystem and that will be used for mount points (so for example if the label is mydrive, the mount point will be /media/mydrive). But probably it won't work on all distros.

I tried it but it did not change anything.

What about modifying this so that if sdb1 is not present, then run sdc1 ?

It would be safer to run a mount command specifying the exact device. You could use the -U option of mount to mount by UUID - or the -L option to mount by label.

The label is a filesystem feature, so use e2label if it's ext3/4 or mlabel if it's fat32, then:

If you prefer UUID, you can get it via:
(Where X is b or c, depending on how your drive is recognized when you run the command.)

My script just uses Thunar to open a directory.

If it can not, I want it to open another directory which in my case is sdc1.

How would mount help a script make decisions on what to do based on what is mounted ?

I need something that can perform a task based on whether an operation failed or not.

Hope that made sense. :-)

I might not be following your intent but here's my thought:

The mount command above just mounts whatever device by label.

The second command attempts to open the directory /mnt (where the root of your drive should be) and thows away any output or error (> /dev/null 2>&1)

I think what you're looking for is "||".
If the first command fails, then the command after "||" is run. Like that?

Edit: Related to the desired commands above, that might also be:
thunar /mnt/sdb1/Linux_Files || thunar /mnt/sdc1/Linux_Files

Using

It opens thunar at /mnt.

I have all volumes mounted at bootup.

Do they have to be unmounted for this to work ?

what is that test.sh? How should we know what caused that error message?
You used the mount command improperly:
remove [ and ], just enter the label itself.
do not add the device to the command, but the mount point (an empty dir)
mount -L label /mount/dir

I made the corrections.

If I manually unmount sdb1

mount -L Backup_Toshiba_Partition /mnt
thunar /mnt > /dev/null 2>&1 || echo "Operation failed."

I get this.

# test.sh
df-FULL: /mnt/sda1: No such file or directory
df-FULL: /mnt/sda2: No such file or directory