July 2005 - Darwin-dev - lists.apple.com

Re: Maximum uid and how to indicate "any user"
by Greg Hurrell 12 Jul '05

12 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com El 12/07/2005, a las 6:08, Mike Smith escribió: 1. Single method with special value used to indicate "any user": - (void)doSomethingWithUser:(long long)uid; - (void)doSomething; - (void)doSomethingWithUser:(uid_t)uid; 3. Single method with additional argument: - (void)doSomething:(uid_t)uid anyUser:(BOOL)flag; - (void)doSomethingWithUser:(uid_t *)uid; Cheers, Greg _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Is there any reason that you can't simply pass another argument? No, no reason. That's another option that I forgot to list. I was just trying to come up with the "cleanest" API with minimal code duplication, but "clean" is always going to be a bit subjective: 2. Separate methods, one for "any user" and another for a specified user: 4. Single method with uid passed by reference, passing NULL pointer for "any user": There are probably some other options too but I don't want to get carried away listing them. For me stylistic questions often come up like this when mixing higher-level code (written in Objective-C) with lower-level APIs... When I first approached the problem, the first style seemed the right way to do it, but now I am not so sure. This email sent to site_archiver(a)lists.apple.com

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Re: Maximum uid and how to indicate "any user"
by Mike Smith 12 Jul '05

12 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jul 11, 2005, at 12:06 PM, darwin-dev-request(a)lists.apple.com wrote: A quick question and a request for a word of advice... Can someone direct me to a header where I can find the maximum possible uid under Darwin? The only reference I can find on the net is this old one: http://sourceforge.net/mailarchive/message.php?msg_id=1673516 Which in turn makes reference to an Apple document which now 404s... http://www.apple.com/macosx/server/pdf/UnderstandingUsingNetInfo.pdf That document apparently says that the maximum uid is 2,147,483,647. The reason I ask is that I am writing some methods which take a uid_t argument and I want to come up with a safe value that can be passed to indicate "any user". Is there any reason that you can't simply pass another argument? "Magic" values are inherently unsafe (bad) for all sorts of reasons. The use of a 64-bit argument is just "hiding" the extra argument in the high bits of another, but without a prototype to save you from messing it up. Better to be explicit about it up front. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: Maximum uid and how to indicate "any user"
by Greg Hurrell 12 Jul '05

12 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com El 11/07/2005, a las 18:24, Jason Townsend escribió: 1. Go with the "long long" suggestion. Cheers, Greg _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… UIDs are 32 bit signed integers as stored in the user records (as you saw with the nobody UID of -2). I would recommend against assuming that any possible 32 bit value means anything special because there are some cases where larger numbers are mapped onto the 32 bit UID space (primarily when integrating with Active Directory). The suggestion of using a long long would be a reasonable approach. To answer your last question, UIDs are what they are and can't be changed without breaking binary compatibility. However, there are already 128 bit GUID/UUIDs present on the system which are now used in Tiger to support nested groups and ACLs. These are stored in the standard hex format for UUIDs, which looks like this: 72DD37F9-1B8F-4BEB-BCBF-7958D7314AF8. They are stored in the GeneratedUID attribute in user and group records (and other record types as well). These IDs are parallel to the existing UIDs and GIDs. Thanks very much for the detailed info, Jason. On the basis of this info I have two options: 2. Forget about using any special value to indicate "any user" and instead break my single method into two separate ones, one for use with a specified uid and another for "any user"... I had only wanted to avoid code duplication by using the same method to do two things, but given the subtleties and complexities of user ids I think I might just have to bite the bullet and split it into two methods. There is not a huge difference here, but I like doing things The Right Way if I can. This email sent to site_archiver(a)lists.apple.com

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Re: Maximum uid and how to indicate "any user"
by Jason Townsend 11 Jul '05

11 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com http://sourceforge.net/mailarchive/message.php?msg_id=1673516 Which in turn makes reference to an Apple document which now 404s... It should be this: http://www.apple.com/server/pdfs/UnderstandingUsingNetInfo.pdf That document apparently says that the maximum uid is 2,147,483,647. Thanks, Nat. To clarify, do you mean declaring the method like so: - (void)theMethod:(long long)uid; -Jason -- Jason Townsend http://www.opendarwin.org/~jtownsend/ _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… On Jul 10, 2005, at 2:25 PM, Greg Hurrell wrote: A quick question and a request for a word of advice... Can someone direct me to a header where I can find the maximum possible uid under Darwin? The only reference I can find on the net is this old one: http://www.apple.com/macosx/server/pdf/UnderstandingUsingNetInfo.pdf The reason I ask is that I am writing some methods which take a uid_t argument and I want to come up with a safe value that can be passed to indicate "any user". In "/usr/include/sys/types.h" uid_t is defined as having type u_int32_t. I notice that on my clean Tiger install user "nobody" has uid -2, but obviously "nobody" and "any user" aren't the same thing. So I am wondering if -1 would be a safe value to use to stand for "any user". On Jul 11, 2005, at 2:39 AM, Greg Hurrell wrote: And then casting to uid_t inside the method before passing the parameter to other functions which expect uid_t type parameters? (And do you think it's likely that Darwin's uid_t will get upsized from uint32 in the future?) UIDs are 32 bit signed integers as stored in the user records (as you saw with the nobody UID of -2). I would recommend against assuming that any possible 32 bit value means anything special because there are some cases where larger numbers are mapped onto the 32 bit UID space (primarily when integrating with Active Directory). The suggestion of using a long long would be a reasonable approach. To answer your last question, UIDs are what they are and can't be changed without breaking binary compatibility. However, there are already 128 bit GUID/UUIDs present on the system which are now used in Tiger to support nested groups and ACLs. These are stored in the standard hex format for UUIDs, which looks like this: 72DD37F9-1B8F-4BEB-BCBF-7958D7314AF8. They are stored in the GeneratedUID attribute in user and group records (and other record types as well). These IDs are parallel to the existing UIDs and GIDs. This email sent to site_archiver(a)lists.apple.com

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Re: Maximum uid and how to indicate "any user"
by Greg Hurrell 11 Jul '05

11 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thanks, Nat. To clarify, do you mean declaring the method like so: - (void)theMethod:(long long)uid; Greg Ciao Nat! _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… And then casting to uid_t inside the method before passing the parameter to other functions which expect uid_t type parameters? (And do you think it's likely that Darwin's uid_t will get upsized from uint32 in the future?) El 11/07/2005, a las 2:36, Nat! escribió: If it's advice you seek, use a long long (64 bit) as an internal parameter. This email sent to site_archiver(a)lists.apple.com

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Maximum uid and how to indicate "any user"
by Greg Hurrell 10 Jul '05

10 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com http://sourceforge.net/mailarchive/message.php?msg_id=1673516 Which in turn makes reference to an Apple document which now 404s... http://www.apple.com/macosx/server/pdf/UnderstandingUsingNetInfo.pdf That document apparently says that the maximum uid is 2,147,483,647. Greg _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… A quick question and a request for a word of advice... Can someone direct me to a header where I can find the maximum possible uid under Darwin? The only reference I can find on the net is this old one: The reason I ask is that I am writing some methods which take a uid_t argument and I want to come up with a safe value that can be passed to indicate "any user". In "/usr/include/sys/types.h" uid_t is defined as having type u_int32_t. I notice that on my clean Tiger install user "nobody" has uid -2, but obviously "nobody" and "any user" aren't the same thing. So I am wondering if -1 would be a safe value to use to stand for "any user". This email sent to site_archiver(a)lists.apple.com

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Re: kern.osrevision
by Daniel Becker 09 Jul '05

09 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jul 9, 2005, at 17:18, Stéphane Sudre wrote: Stupid question: So why is kern.osrevision stuck to 199506? Daniel _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I tend to believe the Darwin source code has been modified between Mac OS X 10.2.8 and Mac OS X 10.4.1. Is this a FreeBSD malediction? According to <http://mail-index.netbsd.org/tech-kern/ 2005/02/04/0010.html>, kern.osrevision gives the BSD release, and 199506 corresponds to 4.4Lite2. This email sent to site_archiver(a)lists.apple.com

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kern.osrevision
by Stéphane Sudre 09 Jul '05

09 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Stupid question: So why is kern.osrevision stuck to 199506? Is this a FreeBSD malediction? _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I tend to believe the Darwin source code has been modified between Mac OS X 10.2.8 and Mac OS X 10.4.1. This email sent to site_archiver(a)lists.apple.com

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Objective-C message logging weirdness
by David Hoerl 08 Jul '05

08 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com I looked at the source for an objective-c runtime file: http://darwinsource.opendarwin.org/10.3/objc4-235/runtime/objc-class.m You can see there two non-static functions: void instrumentObjcMessageSends (BOOL flag) void logObjcMessageSends (ObjCLogProc logProc) However, I get an unresolved reference to logObjcMessageSends. >From my read of the source, you would need to call both functions: instrumentObjcMessageSends(YES); logObjcMessageSends(myProc); Can anyone shed light on this? David _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… [I also downloaded the 10.4.1 source, and these files are the same. For some reason you cannot get at the source for this release as easily.] if I use instrumentObjcMessageSends in my project, it builds and links just fine (static not ZeroLink). What makes this second function so intriguing is that you can specify your own logging function, which could also filter the output based on programmatic runtime criteria. But, without the reference to logObjcMessageSends all is lost. What one DOES get with the first function is a log of EVERY method/class call. In a few seconds I got about 10Megs worth of data. Clearly a filter here would be of great value. This email sent to site_archiver(a)lists.apple.com

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Re: Jag Server and Net Info
by Justin C. Walker 08 Jul '05

08 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jul 7, 2005, at 15:35 , Steffan A. Cline wrote: Regards, Justin -- Justin C. Walker, Curmudgeon at Large Institute for General Semantics ----------- My wife 'n kids 'n dog are gone, I can't get Jesus on the phone, But Ol' Milwaukee's Best is my best friend. ----------- _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I just saw something funky on Jaguar Server. I thought I could hit up the list to see if anyone had an idea. For some reason after a reboot Apple Remote desktop does not come up. I then use the function from the admin tool to update software. I do this and it works fine. Then ARD lets me back in. This is a tad off-topic for the darwin lists. Apple and Omnigroup both have lists dealing with server and admin issues for Mac OS X. You might do better there. This email sent to site_archiver(a)lists.apple.com

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