ulimit is a utility tool to set some limitations of the user process. For example, you can set the maximum core file size by using ulimit -c command.

# It sets the max number of blocks used for the core file.
$ ulimit -c 100000

But ulimit does not show information about other processes. You may want to check the resource limitation put on the running processes. You can check the resource limitation of an arbitrary process by using /proc file system.

$ cat /proc/$PID/limits
Limit                     Soft Limit           Hard Limit           Units
Max cpu time              unlimited            unlimited            seconds
Max file size             unlimited            unlimited            bytes
Max data size             unlimited            unlimited            bytes
Max core file size        0                    unlimited            bytes
...