user limits for 'security'?

I've seen some people saying that user-limits are an essential part of a secure system to prevent local DoS attacks. Given that, should a system call like 'fork' return -EPERM if the user has reached their limit?

My local manpage (SuSE 7.2 system) says this under fork:

ERRORS
EAGAIN fork cannot allocate sufficient memory to copy the
parent's page tables and allocate a task structure for the child.
-----
Should the man page be updated to reflect that EAGAIN is returned
when the user has reached their limit? From a user-monitoring point of view, it might be security relevant to know if a EAGAIN is being returned because the system really is low on resources or if it is a user hitting their limit.

--

The above thoughts and            | I know I don't know the opinions
writings are my own.              | of every part of my company. :-)
L A Walsh, law at sgi.com         | Sr Eng, Trust Technology
01-650-933-5338                   | Core Linux, SGI

I suppose another question related to the first, is 'limit' checking part of the 'standard linux security' that embedded Linux users might find to be a waste of precious code-space?

-l

--

The above thoughts and            | I know I don't know the opinions
writings are my own.              | of every part of my company. :-)
L A Walsh, law at sgi.com         | Sr Eng, Trust Technology
01-650-933-5338                   | Core Linux, SGI