osx man page for sethostid

GETHOSTID(3)						   BSD Library Functions Manual 					      GETHOSTID(3)

NAME
     gethostid, sethostid -- get/set unique identifier of current host

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     long
     gethostid(void);

     void
     sethostid(long hostid);

DESCRIPTION
     The sethostid() function establishes a 32-bit identifier for the current processor.  The id, intended to be unique among all UNIX systems in
     existence, is normally a DARPA Internet address for the local machine.  This call is allowed only to the super-user and is normally performed
     at boot time.

     The gethostid() function returns the 32-bit identifier for the current processor.

     This function has been deprecated.  The hostid should be set or retrieved by use of sysctl(3).

SEE ALSO
     gethostname(3), sysctl(3), sysctl(8)

BUGS
     32 bits for the identifier is too small.

HISTORY
     The gethostid() and sethostid() syscalls appeared in 4.2BSD and were dropped in 4.4BSD.

BSD
								   June 2, 1993 							       BSD