Crontabs *should* be in /var (opinion only, let's not turn this into a
"DO NOT!"  "DO TOO!"-fest), for reasons which I think are probably obvious
-- or at least obvious enough for me to lay good odds that this ground
has been covered before I could reply to this thread.

/var was invented to take some load off /usr, I believe -- moving all
the log files and the like to another filesystem was supposed to help
make /usr a read-only filesystem (of course, this only works if /usr/src
is separately mounted as well AND you're not using this system as a
development system).

Typically, if you don't have enough disk space to warrant a separate root,
/tmp, /usr/src and /var, it probably doesn't matter WHERE you put your
crontabs.  However, for those of us who actually (through hook and crook)
ended up with sufficient disk space, separate filesystems as described
above are a necessity.

Where do crontabs fit in?  Well, they are changing files -- or they can
be changing files.  Miscreants can always be bumped off the system, but
I don't think that's the point (do you follow?).  They, like many other
things, do not belong on the root filesystem (see above for exceptions).
A diatribe on what does belong on the root filesystem is a topic for
another discussion.

The first place I ever remember seeing a crontab file was /usr/lib/crontab.
It contained cron jobs for the world, with different uids being achieved
thru 'su $USER -c ...' commands.

Then 4.3 came out and implemented a username field in the crontab.  This
still didn't "solve the problem" of users other than root adding a crontab
entry.

Then SunOS came out and reorganized the filesystem hierarchy (replete with
/var) and reorganized cron such that /usr/lib/crontab went away and was
replaced with /var/spool/cron/crontabs/$USER.  Users could (theoretically)
have their own crontab files (permissions providing, of course).  /var/...
was the last place I saw the crontab files, even AFTER AT&T and Sun slept
together and Sun gave birth to their mutant child.

That's my ((unsigned long) foo & 0x3) worth...

--
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