ulimit (was: getty/login for callback)

[Richard A. O'Keefe]

In article <120 at mslanpar> pat at mslanpar (Pat "King of the Trenches" Calhoun) writes:
>In article <827 at twwells.uucp>, bill at twwells.uucp (T. William Wells) writes:
>> But it fails to explain why increasing ones ulimit is restricted to root.
>> If ulimit is only a safety belt, there isn't any good reason for preventing
>> one from tightening or loosening it as needed.

>	WARNING: NO SPACE ON DISK 0 PARTITION 0!!! :=)
>	..., it would be useless to have a safety device that could
>	be overridden by anyone. This defeats the purpose of having 
>	a ulimit.  The message above is not a fantasy, but reality,
>	and when it does occur, it's usually a pain to clear out the 
>	files (making sure not to get rid of anything of value!)

Yes, but ulimit doesn't help with that.  (Actually, ulimit
also reports the maximum break, and does some other things too these days.)
Let ulimit be 1M.  All that means is that no one file I create can be
bigger than that.  There is nothing to stop me creating 500 1/2Mb files!
My experience may not be typical, but I don't think I've ever had a disc
fill up on me due to a single file being too big, in every case it has
been too many smallish junk files cluttering up the place.  The only time
I've ever noticed the existence of ulimit has been when uucp has mysteriously
lost or truncated things.  In fact things like news are a good example of how
ulimit fails to help: you get thousands of small files each of which ulimit
is perfectly happy with.

If the default ulimit had been infinity (with ordinary users only being able
to decrease it), any sysadmin who wanted the present state of affairs could
have done it with one line in /etc/profile, and sites that didn't want to
know about it wouldn't have had file transfers die mysteriously.