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

Newbie to Darwin linking issue I think?
by Damien Cooke 04 Jun '05

04 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com I build the two object files as such gcc -g -fPIC -c source/lpmalloc.c -o output/lpmalloc.o gcc -g -fPIC -c source/global.c -o output/global.o This is what I get: ld: for architecture ppc ld: Undefined symbols: _printf libtool: internal link edit command failed Damien _______________________________________________ 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… Sorry for the dumb question. I am porting my malloc to Darwin. I have built it as a shared dynamic library on Solaris. However I am having a large amount of problems with this on OS X 10.4.1 using XCode 2.0 and gcc 4.0 Then I use Libtool as such libtool -dynamic -o bin/liblpmalloc.so output/lpmalloc.o output/global.o I am probably doing something really dumb but any help would be greatly appreciated. This email sent to site_archiver(a)lists.apple.com

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Re: Rookie question
by James Berry 04 Jun '05

04 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jun 4, 2005, at 9:51 AM, Marc Chanliau wrote: -jdb Thanks in advance, Marc _______________________________________________ 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/james%40jberry.us This email sent to james(a)jberry.us _______________________________________________ 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'm new to the Mac. I plan on doing some Java and C development on the Mac. I found my way around with Java, but I have a silly starting problem with C. Simply put, when I compile a C program, I generate its a.out executable, but bash doesn't want to execute it (error: -bash: a.out: command not found). Right now, I don't want to use Xcode (although things seem to be working well using it). Since the current directory is not in your path, you have to specify an explicit path to the executable: ./a.out This email sent to site_archiver(a)lists.apple.com

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Rookie question
by Marc Chanliau 04 Jun '05

04 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com I'm new to the Mac. I plan on doing some Java and C development on the Mac. I found my way around with Java, but I have a silly starting problem with C. Simply put, when I compile a C program, I generate its a.out executable, but bash doesn't want to execute it (error: - bash: a.out: command not found). Right now, I don't want to use Xcode (although things seem to be working well using it). Thanks in advance, Marc _______________________________________________ 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: Unix permissions wacky?
by Gregory Seidman 04 Jun '05

04 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Mail-followup-to: darwin-dev(a)lists.apple.com User-agent: Mutt/1.5.9i On Fri, Jun 03, 2005 at 05:56:50PM -0700, Steve Gehrman wrote: } I have a file that has permission to read for "other", but I can't } copy the file, I get a permission error. } } I must be confused } } Permissions: -rw----rw- (606) } Owner: 0 - root } Group: 501 - steve } } The file is owned by root, but clearly set for others to read. } } The Finder, cp, and other file copying tools give me an error saying } I don't have permission to read. } } Why is this? You will note that the group, steve, has no permissions on the file. This overrides "other" permissions. I assume that you are a member of that group. What those permissions are saying is that the file is read/write for anyone who *isn't* in group steve. } -steve --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… This email sent to site_archiver(a)lists.apple.com

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Unix permissions wacky?
by Steve Gehrman 04 Jun '05

04 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com I must be confused Permissions: -rw----rw- (606) Owner: 0 - root Group: 501 - steve The file is owned by root, but clearly set for others to read. Why is this? -steve _______________________________________________ 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 have a file that has permission to read for "other", but I can't copy the file, I get a permission error. The Finder, cp, and other file copying tools give me an error saying I don't have permission to read. This email sent to site_archiver(a)lists.apple.com

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Re: Named Semaphores
by Mark Stultz 03 Jun '05

03 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Microsoft-Entourage/11.0.0.040405 Ok, I am very very tired :) I don't like to reply to myself, but for archiving purposes, I'd like to point out my finding. I thought semaphore IDs themselves are global, but they are not. So two apps may have a semaphore named "/MySemaphore", and it is only one semaphore. However, the semaphore ids returned by sem_open may be two totally different integer values. Good to know it wasn't something wrong with my code :) Mark Stultz United Developers mstultz(a)udgames.com On 6/3/05 11:59 AM, "Mark Stultz" <mstultz(a)udgames.com> wrote: > I have tried them with and without the slashes with no prevail. Apple's > SharedMemory.app example code doesn't use a slash either. I am totally > confused as to what may be the case. I especially do not know why semaphore > IDs would overlap. It doesn't seem as if they're global. > > > On 6/3/05 11:54 AM, "AgentM" <agentm(a)themactionfaction.com> wrote: > >> Please read: >> http://www.opengroup.org/onlinepubs/007908799/xsh/sem_open.html >> >> Specifically, names that do not begin with a slash results in >> something implementation-dependent. Try a path or just "/test" or "/ >> tmp/test". >> >> On Jun 3, 2005, at 11:42 AM, Mark Stultz wrote: >> >>> (also posted on unix-porting...) >>> If this is posted to the wrong list, please let me know of a more >>> appropriate listing. I am porting a unix program that utilizes named >>> pthreads to lock certain things in one program, and in another "child" >>> program, it sees if it locks for certain tests. >>> >>> I'd like to preface this by saying we are using the 10.2.8 SDK. >>> >>> Since we do not have named pthreads, I am using named semaphores >>> because >>> they are system-wide, and we are only doing locks & try locks. >>> However, >>> when I set up my two programs, they do not recognize each other's >>> semaphore >>> IDs. Some of the IDs even over lap. Here is a snippet of pseudo >>> code I am >>> going by... >>> >>> class NamedSemaphores >>> { >>> public: >>> // Constructor / Destructor >>> NamedSemaphores( const char *name_ = 0 ) >>> { >>> // See if it exists first >>> _semaphoreID = ::sem_open( name_, 0 ); >>> >>> printf("semid = %i\n", (int)_semaphoreID ); >>> >>> if ( ( int )_semaphoreID == SEM_FAILED ) >>> { >>> // Otherwise, create it >>> _semaphoreID = ::sem_open( name_, O_CREAT, 0777, 0 ); >>> } >>> >>> if ( ( int )_semaphoreID == SEM_FAILED ) >>> { >>> printf( "SEM_FAILED\n" ); >>> } >>> } >>> >>> ...continues with more class functions... >>> >>> private: >>> sem_t *_semaphoreID; >>> } >>> >>> I had to edit that really quick, so the syntax may contain a typo or >>> something. At any rate, both programs are pretty much identical, >>> and they >>> are both calling a: >>> >>> NamedSemaphores *mySemaphore; >>> MySemaphore = new NamedSemaphores( "TEST" ); >>> >>> Obviously I am not using that string, but more like 5 different >>> strings. >>> Program A might return semaphoreID's of: 4, 5, 6, 7, and 8. >>> Program B >>> might return semaphoreID's of 7, 8, 9, 10, and 11. They do not >>> recognize >>> identical strings, and they also overlap certain semaphoreIDs. >>> >>> Any clues as to what might be happening? >>> >>> Mark Stultz >>> United Developers >>> mstultz(a)udgames.com >>> >>> _______________________________________________ >>> Do not post admin requests to the list. They will be ignored. >>> Unix-porting mailing list (Unix-porting(a)lists.apple.com) >>> Help/Unsubscribe/Update your Subscription: >>> http://lists.apple.com/mailman/options/unix-porting/mstultz% >>> 40udgames.com >>> >>> This email sent to mstultz(a)udgames.com >>> >>> _______________________________________________ >>> 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/agentm% >>> 40themactionfaction.com >>> >>> This email sent to agentm(a)themactionfaction.com >>> >> >> |-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- >> AgentM >> agentm(a)themactionfaction.com >> |-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- >> > > > Mark Stultz > United Developers > mstultz(a)udgames.com > > _______________________________________________ > 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/mstultz%40udgames.com > > This email sent to mstultz(a)udgames.com _______________________________________________ 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: Named Semaphores
by Mark Stultz 03 Jun '05

03 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Microsoft-Entourage/11.0.0.040405 I have tried them with and without the slashes with no prevail. Apple's SharedMemory.app example code doesn't use a slash either. I am totally confused as to what may be the case. I especially do not know why semaphore IDs would overlap. It doesn't seem as if they're global. On 6/3/05 11:54 AM, "AgentM" <agentm(a)themactionfaction.com> wrote: > Please read: > http://www.opengroup.org/onlinepubs/007908799/xsh/sem_open.html > > Specifically, names that do not begin with a slash results in > something implementation-dependent. Try a path or just "/test" or "/ > tmp/test". > > On Jun 3, 2005, at 11:42 AM, Mark Stultz wrote: > >> (also posted on unix-porting...) >> If this is posted to the wrong list, please let me know of a more >> appropriate listing. I am porting a unix program that utilizes named >> pthreads to lock certain things in one program, and in another "child" >> program, it sees if it locks for certain tests. >> >> I'd like to preface this by saying we are using the 10.2.8 SDK. >> >> Since we do not have named pthreads, I am using named semaphores >> because >> they are system-wide, and we are only doing locks & try locks. >> However, >> when I set up my two programs, they do not recognize each other's >> semaphore >> IDs. Some of the IDs even over lap. Here is a snippet of pseudo >> code I am >> going by... >> >> class NamedSemaphores >> { >> public: >> // Constructor / Destructor >> NamedSemaphores( const char *name_ = 0 ) >> { >> // See if it exists first >> _semaphoreID = ::sem_open( name_, 0 ); >> >> printf("semid = %i\n", (int)_semaphoreID ); >> >> if ( ( int )_semaphoreID == SEM_FAILED ) >> { >> // Otherwise, create it >> _semaphoreID = ::sem_open( name_, O_CREAT, 0777, 0 ); >> } >> >> if ( ( int )_semaphoreID == SEM_FAILED ) >> { >> printf( "SEM_FAILED\n" ); >> } >> } >> >> ...continues with more class functions... >> >> private: >> sem_t *_semaphoreID; >> } >> >> I had to edit that really quick, so the syntax may contain a typo or >> something. At any rate, both programs are pretty much identical, >> and they >> are both calling a: >> >> NamedSemaphores *mySemaphore; >> MySemaphore = new NamedSemaphores( "TEST" ); >> >> Obviously I am not using that string, but more like 5 different >> strings. >> Program A might return semaphoreID's of: 4, 5, 6, 7, and 8. >> Program B >> might return semaphoreID's of 7, 8, 9, 10, and 11. They do not >> recognize >> identical strings, and they also overlap certain semaphoreIDs. >> >> Any clues as to what might be happening? >> >> Mark Stultz >> United Developers >> mstultz(a)udgames.com >> >> _______________________________________________ >> Do not post admin requests to the list. They will be ignored. >> Unix-porting mailing list (Unix-porting(a)lists.apple.com) >> Help/Unsubscribe/Update your Subscription: >> http://lists.apple.com/mailman/options/unix-porting/mstultz% >> 40udgames.com >> >> This email sent to mstultz(a)udgames.com >> >> _______________________________________________ >> 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/agentm% >> 40themactionfaction.com >> >> This email sent to agentm(a)themactionfaction.com >> > > |-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- > AgentM > agentm(a)themactionfaction.com > |-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- > Mark Stultz United Developers mstultz(a)udgames.com _______________________________________________ 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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Design of vn_getpath (was Re: fsevents oddities)
by Hamish Allan 03 Jun '05

03 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 2 Jun 2005, at 05:16, Mike Smith wrote: I'm not sure I understand how MOU is relevant to this. Best wishes, Hamish _______________________________________________ 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 But there is no file /Users/hamish/bar/foo.txt, and nor has there ever been, so something is wrong with the caching. Whatever part of the system is caching foo.txt shouldn't be doing so once the write to bar/bar.txt has happened. And why, even after I've removed foo.txt and imported bar/bar.txt, hasn't it been updated yet in line 20? foo.txt and bar.txt are the same file; it just has two names. Only one of those names can be cached; in this case, it's the one by which the file was first looked up. I really meant to imply the question, "why would the cache not be updated with the name by which the file was *most recently* looked up?" Why would any one name be more correct than any other? It's a losing game, unfortunately. Specifically, I have demonstrated a case where the parent vnode is updated without updating the cached filename, leading to a never- existent path /Users/hamish/bar/foo.txt, in which MRU would be more correct. Solitaire is also a losing game, but there are ways that you can play it which maximise your chances of winning. Whereas with the current situation you remember that the node was once looked up as bar.txt under foo, and provide that pathname whether or not it still exists (even if a currently existing pathname, e.g., quxx.txt under baz, has been used more recently). This is slightly less work for considerably less (indeed, arguably negative) return. It's O(1) work rather than O(N) work, and for the common case (i.e. where nobody is using hardlinks) it works well enough. For the common case (i.e. where nobody is using hardlinks) my suggestion is O(1). "It works well enough" is assuming the consequent -- this thread is about the cost/benefit tradeoff, and I think that misinformation is arguably less useful than no information. I think that "all that" is perhaps touchingly naive, but yes in theory there is no reason why multiple parent associations could not be maintained, however this is a lot of work for overall very little return. You might say the same about providing *any* sort of vn_getpath() operation. As far as I can tell I am not suggesting rocket science? Or am I underestimating the cost of implementing what I would consider to be a decent benefit? In providing *any* pathname for an extant vnode, the kernel is already making a dangerous guarantee. Encouraging further use of the interface just makes the consequences worse. All that the current implementation guarantees is that at some point, components of the returned path were components of a path or paths that once existed to a given vnode. Not even that the returned path was ever a path to the given vnode. What my suggestion guarantees is that at calling time, there existed such-and-such a path to a given vnode. Where's the danger in that? At the very least, surely the current caching mechanism should freshen the cache more often than it does? The tradeoffs between MRU and MOU are so bad that first-come is, in the end, no worse. smime.p7s

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Named Semaphores
by Mark Stultz 03 Jun '05

03 Jun '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Microsoft-Entourage/11.0.0.040405 (also posted on unix-porting...) If this is posted to the wrong list, please let me know of a more appropriate listing. I am porting a unix program that utilizes named pthreads to lock certain things in one program, and in another "child" program, it sees if it locks for certain tests. I'd like to preface this by saying we are using the 10.2.8 SDK. Since we do not have named pthreads, I am using named semaphores because they are system-wide, and we are only doing locks & try locks. However, when I set up my two programs, they do not recognize each other's semaphore IDs. Some of the IDs even over lap. Here is a snippet of pseudo code I am going by... class NamedSemaphores { public: // Constructor / Destructor NamedSemaphores( const char *name_ = 0 ) { // See if it exists first _semaphoreID = ::sem_open( name_, 0 ); printf("semid = %i\n", (int)_semaphoreID ); if ( ( int )_semaphoreID == SEM_FAILED ) { // Otherwise, create it _semaphoreID = ::sem_open( name_, O_CREAT, 0777, 0 ); } if ( ( int )_semaphoreID == SEM_FAILED ) { printf( "SEM_FAILED\n" ); } } ...continues with more class functions... private: sem_t *_semaphoreID; } I had to edit that really quick, so the syntax may contain a typo or something. At any rate, both programs are pretty much identical, and they are both calling a: NamedSemaphores *mySemaphore; MySemaphore = new NamedSemaphores( "TEST" ); Obviously I am not using that string, but more like 5 different strings. Program A might return semaphoreID's of: 4, 5, 6, 7, and 8. Program B might return semaphoreID's of 7, 8, 9, 10, and 11. They do not recognize identical strings, and they also overlap certain semaphoreIDs. Any clues as to what might be happening? Mark Stultz United Developers mstultz(a)udgames.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Unix-porting mailing list (Unix-porting(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/unix-porting/mstultz%40udgames.com This email sent to mstultz(a)udgames.com _______________________________________________ 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: Darwin 8.0 on x86 and SMP (Dual CPU)
by Alexey V. Medvedev 03 Jun '05

03 Jun '05

site_archiver(a)lists.apple.com Delivered-To: Darwin-dev(a)lists.apple.com Organization: GDT Software Group On Thu, 2 Jun 2005 11:57:36 -0700 Shantonu Sen <ssen(a)opendarwin.org> wrote: > The larger question is probably "why are you asking about SMP support > on Darwin x86". If you are expecting high or even reasonable > performance (compared to Linux or FreeBSD), you're probably not > installing Darwin for the right reasons. Darwin x86 is not about > performance or peripheral support. First of all, I just want to make experiments, not to use it for production. I can understand poor peripheral support, but as to bad performance -- it was quite surprising to me. Is there good reasons for Darwin x86 to be less efficient than Darwin PPC? For my experiments I need only good performance of thread scheduler, malloc, IPC and probably TCP/IP stack + Gigabit Ethernet driver. Can't see why x86 port is sure to have bad performance in this case. If it's offtopic there, I'm ready to go away. -- Alexey _______________________________________________ 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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