shtool-mdate(1) on Linux
The text 43c213eb4310, as Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze) shipped it.
GNU shtool pretty-print last modification time
Flags it lists
-
--digits -
--field-sep -
--newline -
--order -
--shorten -
--zero -
-d -
-f -
-n -
-o -
-s -
-z