Internal Program Version: fcron 3.3.1

Fcron is a periodical command scheduler which aims at replacing Vixie Cron,
so it implements most of its functionalities. 

But fcron makes no assumptions on whether your system is running all the 
time or regularly : you can, for instance, tell fcron to execute tasks 
every x hours y minutes of system up time or to do a job only once in a 
specified interval of time.

Fcron has also much more functionalities : you can also set a nice value 
to a job, run it depending on the system load average and much more.

https://fcron.free.fr