CVS commit: src/usr.sbin/cron

["Perry E. Metzger" <perry%netbsd.org@localhost>]

Module Name:    src
Committed By:   perry
Date:           Sat Apr  4 16:05:10 UTC 2009

Modified Files:
        src/usr.sbin/cron: crontab.5 entry.c

Log Message:
New feature: "?" for time specifications, means a single time selected at
random from within the range at file read time. Very useful if you
want to avoid having a fleet of machines melt a server by all trying to
contact it at a precise time every morning. See docs for details.

Reviewed by: christos, apb, vixie, others.

XXX apb suggests, quite reasonably, that ?10-16/2 should mean
something like 10,12,14,16 or 11,13,15. I'm too lazy to do it right
now, but it should be done.

XXX vixie suggests, quite reasonably, that if you're using "?" one
should delay randomly by 0-59 seconds. In the modern NTP world, you
could imagine that with a million well synchronized machines the
second just at the minute would be hit quite hard. I'm too lazy to do
it right now, but it should be done.

XXX cron needs to be updated to Vixie's cron 4.1 code.


To generate a diff of this commit:
cvs rdiff -u -r1.11 -r1.12 src/usr.sbin/cron/crontab.5
cvs rdiff -u -r1.9 -r1.10 src/usr.sbin/cron/entry.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.