Wolfgang Solfrank says:
...
> This is one of the big jokes in slowlaris.  Same as with alias, bg, cd,
> fg, hash, jobs, read, umask, unalias and wait.  They blindly linked the
> same shell script with the names of all shell builtin commands.
> 
> All of the above mentioned commands don't make sense when called in a
> subprocess, as they would work on the subprocess and not change anything
> in the calling shell process which is why they were built into the shell
> in the first place.
> 
> (Granted, there are now a few builtins in newer shells like e.g. test,
> that are only builtin for speed purposes, and those make perfect sense
> to run in a subprocess).
...

Yeah, I wondered about that, never used ulimits so I was not aware how
they worked, i.e. via the environment.  Quite right it's a shell
script.  I guess maybe the Sun people would make the bogus argument
that it's nice for csh users to be able to "ulimit -a", same with
reporting aliases.

James