One thing that's always annoyed me about cron is how it handles the weekday field differently from the other fields. The first four fields, minute, hour, day-of-month, and month, are logically ANDed, but the day-of-month and weekday fields are ORed.
The man page describes the behavior, but does not explain the reasoning behind it: > Note: The day of a command's execution can be specified by two fields -- > day of month, and day of week. If both fields are restricted (ie, are > not *), the command will be run when either field matches the current > time. For example, ``30 4 1,15 * 5'' would cause a command to be run at > 4:30 am on the 1st and 15th of each month, plus every Friday. I've looked for an explanation for this in the past, but I've never had any luck finding one. Making this a special case makes the code needlessly more complicated and fragile, and it sacrifices useful functionality; if the weekday had been ANDed like the other fields, it would be trivially easy to specify things like "third Wednesday of the month". I'm unable to find or think of a use case that would make the special behavior useful, and I have to wonder why it was designed this way. Can anyone point me to the original author's thoughts on this? -- John Abreau / Executive Director, Boston Linux & Unix Email j...@blu.org / WWW http://www.abreau.net / PGP-Key-ID 0xD5C7B5D9 PGP-Key-Fingerprint 72 FB 39 4F 3C 3B D6 5B E0 C8 5A 6E F1 2C BE 99 _______________________________________________ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
