gethostid

GETHOSTID(2)		  Linux Programmer’s Manual		 GETHOSTID(2)



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

SYNOPSIS
       #include <unistd.h>

       long gethostid(void);
       int sethostid(long hostid);

DESCRIPTION
       Get or set a unique 32-bit identifier for the  current  machine.	  The
       32-bit  identifier  is intended to be unique among all UNIX systems in
       existence. This normally resembles the Internet address for the	local
       machine, as returned by gethostbyname(3), and thus usually never needs
       to be set.

       The sethostid call is restricted to the superuser.

       The hostid argument is stored in the file /etc/hostid.

RETURN VALUE
       gethostid returns the 32-bit identifier for the current host as set by
       sethostid(2).

CONFORMING TO
       4.2BSD.	 These	functions  were	 dropped in 4.4BSD.  POSIX.1 does not
       define these functions,	but  ISO/IEC  9945-1:1990  mentions  them  in
       B.4.4.1.	 SVr4 includes gethostid but not sethostid.

FILES
       /etc/hostid

EXAMPLE
       id = gethostid ();

       /* This is a no-op unless unsigned int is wider than 32 bits.  */
       id &= 0xffffffff;

SEE ALSO
       hostid(1), gethostbyname(3)



Linux 0.99.13			  1993-11-29			 GETHOSTID(2)