2006-10-26 Havoc Pennington <hp@redhat.com>

	* doc/dbus-specification.xml: clarify the UUID text slightly

	* dbus/dbus-sysdeps-pthread.c: check for and mostly abort on
	pthread errors. Add DBusMutexPThread and DBusCondVarPThread
	in preparation for being able to extend them for e.g. recursive
	mutexes.

1 files changed, 14 insertions, 8 deletions

diff --git a/doc/dbus-specification.xml b/doc/dbus-specification.xml
index 977734d7..1e4ac4f5 100644
--- a/doc/dbus-specification.xml
+++ b/doc/dbus-specification.xml
@@ -2311,11 +2311,24 @@
         UUID representing the identity of the machine the process is running on.
         This UUID must be the same for all processes on a single system at least
         until that system next reboots. It should be the same across reboots 
-        if possible, but may change due to reconfiguration or hardware changes.
+        if possible, but this is not always possible to implement and is not 
+        guaranteed.
         It does not matter which object path a GetMachineId is sent to.  The
         reference implementation handles this method automatically.
       </para>
       <para>
+        The UUID is intended to be per-instance-of-the-operating-system, so may represent
+        a virtual machine running on a hypervisor, rather than a physical machine.
+        Basically if two processes see the same UUID, they should also see the same
+        shared memory, UNIX domain sockets, process IDs, and other features that require 
+        a running OS kernel in common between the processes.
+      </para>
+      <para>
+        The UUID is often used where other programs might use a hostname. Hostnames 
+        can change without rebooting, however, or just be "localhost" - so the UUID
+        is more robust.
+      </para>
+      <para>
         The UUID must contain 128 bits of data and be hex-encoded (meaning, the hex 
         string contains 32 ASCII characters). The hex-encoded string may not contain 
         hyphens or other non-hex-digit characters, and it must be exactly 32 characters long.
@@ -2323,13 +2336,6 @@
         since the UNIX epoch in the last 32 bits of the UUID, and to put randomly-generated bits
         in the first 96 bits of the UUID.
       </para>
-      <para>
-        The UUID is intended to be per-instance-of-the-operating-system, so may represent
-        a virtual machine running on a hypervisor, rather than a physical machine.
-        Basically if two processes see the same UUID, they should also see the same
-        shared memory, UNIX domain sockets, process IDs, and other features that require 
-        a running OS kernel in common between the processes.
-      </para>
     </sect2>
 
     <sect2 id="standard-interfaces-introspectable">