The documentation for hostname and hostid was missing from
coreutils 8.10 texinfo documentation. While not documenting hostname
could be argued, the man page of hostid directly refers to the
non-existing texinfo documentation.

Index: doc/coreutils.texi
===================================================================
--- doc/coreutils.texi.orig	2011-04-01 13:46:18.000000000 +0200
+++ doc/coreutils.texi	2011-04-01 14:08:23.423850965 +0200
@@ -65,6 +65,7 @@
 * fold: (coreutils)fold invocation.             Wrap long input lines.
 * groups: (coreutils)groups invocation.         Print group names a user is in.
 * head: (coreutils)head invocation.             Output the first part of files.
+* hostid: (coreutils)hostid invocation.         Print numeric host identifier.
 * id: (coreutils)id invocation.                 Print user identity.
 * install: (coreutils)install invocation.       Copy and change attributes.
 * join: (coreutils)join invocation.             Join lines on a common field.
@@ -195,7 +196,7 @@ Free Documentation License''.
 * File name manipulation::       dirname basename pathchk mktemp
 * Working context::              pwd stty printenv tty
 * User information::             id logname whoami groups users who
-* System context::               date arch nproc uname uptime
+* System context::               date arch nproc uname uptime hostname hostid
 * SELinux context::              chcon runcon
 * Modified command invocation::  chroot env nice nohup stdbuf su timeout
 * Process control::              kill
@@ -413,6 +414,8 @@ System context
 * nproc invocation::             Print the number of processors
 * uname invocation::             Print system information
 * uptime invocation::            Print system uptime and load
+* hostname invocation::          Print or set system name
+* hostid invocation::            Print numeric host identifier.
 
 @command{date}: Print or set system date and time
 
@@ -13758,6 +13761,8 @@ information.
 * nproc invocation::            Print the number of processors.
 * uname invocation::            Print system information.
 * uptime invocation::           Print system uptime and load.
+* hostname invocation::         Print or set system name.
+* hostid invocation::           Print numeric host identifier.
 @end menu
 
 @node date invocation
@@ -14610,6 +14615,55 @@ also include processes in the uninterrup
 those processes which are waiting for disk I/O).  The Linux kernel
 includes uninterruptible processes.
 
+@node hostname invocation
+@section @command{hostname}: Print or set system name
+
+@pindex hostname
+@cindex setting the hostname
+@cindex printing the hostname
+@cindex system name, printing
+@cindex appropriate privileges
+
+With no arguments, @command{hostname} prints the name of the current host
+system.  With one argument, it sets the current host name to the
+specified string.  You must have appropriate privileges to set the host
+name.  Synopsis:
+
+@example
+hostname [@var{name}]
+@end example
+
+The only options are @option{--help} and @option{--version}.  @xref{Common
+options}.
+
+@exitstatus
+
+
+@node hostid invocation
+@section @command{hostid}: Print numeric host identifier.
+
+@pindex hostid
+@cindex printing the host identifier
+
+@command{hostid} prints the numeric identifier of the current host
+in hexadecimal.  This command accepts no arguments.
+The only options are @option{--help} and @option{--version}.
+@xref{Common options}.
+
+For example, here's what it prints on one system I use:
+
+@example
+$ hostid
+1bac013d
+@end example
+
+On that system, the 32-bit quantity happens to be closely
+related to the system's Internet address, but that isn't always
+the case.
+
+@exitstatus
+
+
 @node SELinux context
 @chapter SELinux context