+++ /dev/null
-.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu)
-.\"
-.\" Updated with additions from Mitchum DSouza <m.dsouza@mrc-apu.cam.ac.uk>
-.\" Portions Copyright 1993 Mitchum DSouza <m.dsouza@mrc-apu.cam.ac.uk>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" Modified Tue Oct 22 00:22:35 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
-.TH GETHOSTID 3 2010-09-20 "Linux" "Linux Programmer's Manual"
-.SH NAME
-gethostid, sethostid \- get or set the unique identifier of the current host
-.SH SYNOPSIS
-.B #include <unistd.h>
-.sp
-.B long gethostid(void);
-.br
-.BI "int sethostid(long " hostid );
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.ad l
-.br
-.BR gethostid ():
-.RS 4
-_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
-_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
-.RE
-.BR sethostid ():
-.RS 4
-_BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE\ <\ 500)
-.RE
-.ad b
-.SH DESCRIPTION
-.BR gethostid ()
-and
-.BR sethostid ()
-respectively 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
-.BR gethostbyname (3),
-and thus usually never needs to be set.
-
-The
-.BR sethostid ()
-call is restricted to the superuser.
-.SH RETURN VALUE
-.BR gethostid ()
-returns the 32-bit identifier for the current host as set by
-.BR sethostid ().
-
-On success,
-.BR sethostid ()
-returns 0; on error, \-1 is returned, and
-.I errno
-is set to indicate the error.
-.SH ERRORS
-.BR sethostid ()
-can fail with the following errors:
-.TP
-.B EACCES
-The caller did not have permission to write to the file used
-to store the host ID.
-.TP
-.B EPERM
-The calling process's effective user or group ID is not the same
-as its corresponding real ID.
-.SH CONFORMING TO
-4.2BSD; these functions were dropped in 4.4BSD.
-SVr4 includes
-.BR gethostid ()
-but not
-.BR sethostid ().
-POSIX.1-2001 specifies
-.BR gethostid ()
-but not
-.BR sethostid ().
-.SH NOTES
-In the glibc implementation, the
-.I hostid
-is stored in the file
-.IR /etc/hostid .
-(In glibc versions before 2.2, the file
-.I /var/adm/hostid
-was used.)
-.\" libc5 used /etc/hostid; libc4 didn't have these functions
-
-In the glibc implementation, if
-.BR gethostid ()
-cannot open the file containing the host ID,
-then it obtains the hostname using
-.BR gethostname (2),
-passes that hostname to
-.BR gethostbyname_r (3)
-in order to obtain the host's IPv4 address,
-and returns a value obtained by bit-twiddling the IPv4 address.
-(This value may not be unique.)
-.SH BUGS
-It is impossible to ensure that the identifier is globally unique.
-.SH SEE ALSO
-.BR hostid (1),
-.BR gethostbyname (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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