They can be used safely. You just have to pick one and stay with
it. (And no, no-clobber hack does not help here. Or do you have
specific application where no-clobber hack helps?)
Anyway, with wildcarded dates, no-clobber is a problem -- because you
need to kill the alarm after you waken up, or it will repeat.
Pavel
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(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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