Re: [Qemu-devel] [PATCH v2 4/6] Use libuuid if available.

[Andreas Färber]

Am 25.08.2008 um 11:58 schrieb Gleb Natapov:

> If libuuid is available use it for UUID generation in case a user  
> does not
> provide one.
>
> Signed-off-by: Gleb Natapov <address@hidden>
> ---

I don't remember hearing an answer on why this is necessary. For which  
use case can't you just either use -uuid `uuidgen` or a hardcoded  
default value like the Slirp IPv4 subnet?

With your patch, not specifying a UUID would generate new random UUIDs  
even for a single disk image, which doesn't sound good (think of  
placing a Windows volume into a different PC on each boot) and is  
inconsistent with previous QEMU policies. We're not talking about a  
rare corner case here - it's a new option, so all legacy scripts and  
setups would be affected by this non-deterministic behavioral change.

In case you didn't find the thread I referenced earlier, here's a link:
http://www.mail-archive.com/address@hidden/msg15809.html

Andreas