Set the com.sun:auto-snap-desc property on each snapshot to an
arbitrary value. On Solaris, this property is set to the dash
character by default -- which is convention for NULL -- but it
can contain an FMRI status comment or other user data.
An alternative implementation of the zfs-auto-snapshot service for Linux.
This program is a posixly correct bourne shell script. It depends only on
the zfs utilities and cron, and can run in the dash shell.