freebsd man page for ulimit

ULIMIT(3)						   BSD Library Functions Manual 						 ULIMIT(3)

NAME
     ulimit -- get and set process limits

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ulimit.h>

     long
     ulimit(int cmd, ...);

DESCRIPTION
     The ulimit() function will get and set process limits.  Currently this is limited to the maximum file size.  The cmd argument is one of the
     following:

     UL_GETFSIZE  will return the maximum file size in units of 512 blocks of the current process.

     UL_SETFSIZE  will attempt to set the maximum file size of the current process and its children with the second argument expressed as a long.

RETURN VALUES
     Upon successful completion, ulimit() returns the value requested; otherwise the value -1 is returned and the global variable errno is set to
     indicate the error.

ERRORS
     The ulimit() function will fail if:

     [EINVAL]		The command specified was invalid.

     [EPERM]		The limit specified to ulimit() would have raised the maximum limit value, and the caller is not the super-user.

SEE ALSO
     getrlimit(2)

STANDARDS
     The ulimit() function conforms to IEEE Std 1003.1-2001 (``POSIX.1'').

HISTORY
     The ulimit() function first appeared in FreeBSD 5.0.

BUGS
     The ulimit() function provides limited precision for setting and retrieving process limits.  If there is a need for greater precision than
     the type long provides, the getrlimit(2) and setrlimit(2) functions should be considered.

BSD
								  January 4, 2003							       BSD