Getting a unique id from a unix-like system

Question

I want to get from any Unix-like system (if this is possible) a unique id that will be persistent every time my application runs in the same machine. If it is possible, I wa

Answer 1

How about the UUID of the root filesystem? You can get the root filesystem device from /etc/fstab, either by manually parsing the file or by using getfsent (3) or getfsfile (3). Once you have the device, you can get the UUID by either checking the links in /dev/disk/by-uuid or from the blkid command.