The posix_getpwuid function returns an array describing an entry in the user database
based on a given user ID. The elements of the array are dir, gecos, gid, name, passwd,
shell, and uid. These are the same elements returned by posix_getpwnam.
array posix_getrlimit()
The posix_getrlimit function returns an array describing system resource usage. The
array contains elements that begin with hard or soft followed by a space and one of the
following limit names: core, cpu, data, filesize, maxproc, memlock, openfiles, rss,
stack, totalmem, virtualmem.
Figure 8-6. posix_getrlimit.integer posix_getsid()