So many formats, So few packages

[Jordan K. Hubbard]

On Apr 11, 2011, at 1:43 AM, Rainer Müller wrote:

> On 2011-04-07 22:03 , Jeff Johnson wrote:
>> Does MacPorts have a well-defined and documented means of attaching the "new uid's" to
>> ports?
> 
> Can you explain that a bit more? I know what a UUID is, but how are they
> being used in Mac OS X binaries or where can I read up on that?

I don't know what Jeff is doing with UUIDs (probably something unnatural ;-) ) but I can say something about how they're used in Mac OS X.   They're basically signed in to binaries using the codesign(1) command (see -i flag) and uniquely identify that binary from the perspective of ongoing continuity.  Let's say, for example, that the binary has some keychain items associated with it.  The UUID ties the application to the keychain items such that when you update the binary, as long as you use the same identity, the updated version of application FOO version BAR can still use the keychain items (without an authorization prompt) from FOO version BAR - 1.   That's not the only thing UUIDs are used for, but it's probably the easiest scenario to explain.

- Jordan