Just getting random GUIDs under Win-XP
Guenther Brunthaler
I have a severe problem: Since I've migrated from NT4 to XP, the
CoCreateGUID function only seems to return random GUIDs!
Because random GUIDs do not include the MAC of the system's NIC, they
cannot guaranteed to be truly unique in space and time (although I
have to admit that the chance for a collision is still rather small).
The GUIDGEN.EXE tool that is shipped with MSVC also reflects this
strange behavior: Each newly generated GUID seems to be completely
random without any reference to my NIC or the current date/time.
I was also able to repeat this effect on the native XP installation of
a friend of mine, so it seems to be a generic XP problem.
Can anyone tell me why this does happen - and what I can do about it?
Greetings,
Guenther
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Guenther Brunthaler
<gbrun...@nospam.geocities.com> wrote:
I solved the problem for myself:
Microsoft has changed the semantics of CoCreateGUID starting with W2K;
now the function UuidCreateSequential from rpcrt4.dll must be used for
the old semantics.