Test if a file is on NFS?

With GNU stat on Linux at least:

stat -fc %T /path/to/the/file

It works for nfs and most common filesystems, but not for all of them.

This is kinda random, but not terribly dirty:

df -TP /path/to/your/file | tail -1 | awk '{print $2}'

It will break if your filesystem name has spaces in it.