KISS tools for make snapshots in a Btrfs filesystem.

SSKit is made up of several small programs that work together, functioning
as one. Currently:

• sskd: Daemon for making snapshots.
• ssmk: Makes snapshots only if necessary.
• sscl: Clean snapshots when is necessary.

Additionally, it also integrates the following tools:

• ssct: Shows Creation time and Changed time of a snapshot.
• ssst: Shows some statics of interest. (Not implemented yet)
• ssgui: Graphic user interface. (Not implemented yet)

On startup sskd loads /etc/sstab into memory and creates snapshots, that are
stored in the specified pool directory.

# subvolume    pool               frequency    quota

/              /backup/root/boot  0            30
/              /backup/root/diary 1d           30
/home          /backup/home/30m   30m          20

In every execution loop, if more time than indicated by the frequency has
passed, a new snapshot of the subvolume will be created inside of its own
pool, until reach the quota, and then, when quota were overpassed, it will
deletes the oldest snapshot until fit to the quota.

Is the daemon. Loads /etc/sstab into memory and runs first ssmk and then
sscl for each line.

Creates a snapshot of the subvolume in the specified directory, only if the
minimum frequency time is met. And only if there have been changes. The
snapshot name is automatically set in the format +%Y-%m-%d_%H-%M-%S.

Delete the oldest snapshots until the quota is met.

Shows when subvolume was created and when an inode in the subvolume was last
change.

Show snapshot statistics (Not implemented yet).

• System calls.

See changelog