I multi-boot several configurations &/or releases of Debian. I will run identical test scripts on each. I want to store the results in a common logging file. I can set up an appropriate environment with a custom fstab containing:
# create a common area LABEL=owlcommon /home/richard/Documents/tst_common vfat user,rw,umask=000 0 0 # a dummy mount labeled to show which instance LABEL=dummy /home/richard/Documents/where/sda14 ext4 user,ro 0 0
The first statement gives me a directory usable by all. The second tells me where I am by using: ls /home/richard/Documents/where in any test script.