Comment Timer units -- Cron as a separate concern (Score 1) 469
Cron has specific semantics about batch scheduling of tasks or periodic, non-overlapping tasks. It runs them in a particular execution context, and I like knowing that it logs it an very identifiable way (both through the audit log and cron logs). Syntax of a cron job file is very low on the totem pole of things I care about when it comes to batch or periodic tasks. This is not a trivial task, as you say, and it deserves a closed system, especially if it must be targeted by cross-platform products needing such a facility.