as	Max address space
cpu	CPU time in seconds
fsize	Maximum filesize
data	max data size
stack	max stack size
core	max core file size
rss	max resident set size
nproc	max number of processes
nofile	max number of open files
memlock	max locked-in-memory address

When the process hits a limit POSIX systems normally send the process a signal that terminates it. These signals may be caught using SWI-Prolog's on_signal/3 primitive. The code below illustrates this behaviour. Please note that asynchronous signal handling is dangerous, especially when using threads. 100% fail-safe operation cannot be guaranteed, but this procedure will inform the user properly `most of the time'.

rlimit_demo :-
        rlimit(cpu, _, 2),
        on_signal(xcpu, _, cpu_exceeded),
        ( repeat, fail ).

cpu_exceeded(_Sig) :-
        format(user_error, 'CPU time exceeded~n', []),
        halt(1).