Ulimit and launchctl both fail to restrict maximum file size

Question

I've submitted a bug report, but I figured I'd open this up to the community.  I can't seem to find any way to set restrictions on the maximum file size that can be created on OS X.   I've tested both Snow Leopard and Lion.
*** Ulimit method:
$ ulimit -f 100000
$ ulimit -f
100000
$ dd if=/dev/zero of=/tmp/zero
Filesize limit exceeded: 25
$ ls -al /tmp/zero
-rw-r--r--  1 admin  wheel  102400000 Jul  5 08:23 /tmp/zero
$ ulimit -f
unlimited
*** launchctl method:
$ launchctl limit filesize 100000
$ launchctl limit filesize
filesize    100000         100000        
$ dd if=/dev/zero of=/tmp/zero
dd: /tmp/zero: No space left on device
54883985+0 records in
54883984+0 records out
28100599808 bytes transferred in 683.205935 secs (41130497 bytes/sec)
$ ls -al /tmp/zero
-rw-r--r--  1 admin  wheel  28100599808 Jul  5 08:36 /tmp/zero
$ launchctl limit filesize
filesize    unlimited      100000        
In the first case, a limit does get set.  But when the first launched application returns control back to the terminal, the limit gets reset back to "unlimited".    In the second case, launchctl does appear to list a soft and hard limit for "filesize", however it does not stop dd from filling up the disk.  Running launchctl again shows an "unlimited" soft limit, but the hard limit remains.
I've even tried setting a persistent, global limit via /etc/launchd.conf.   launchctl reports this limit, however there is nothing stopping huge files from being created.
I do think that this is a bug on OS X, but perhaps there's something I'm overlooking?  If it is a bug, is there some workaround that I can use?
Thanks
-WD

Answer 1

There are no file size limits to the software beyond what would be imposed by the operating system itself and the file format of the drive.
So...assuming you have enough drive space, something else is going on.