September 2011 - Darwin-dev

Questions about SMJobBless
by Eric Gorr 30 Sep '11

30 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.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: Still more pty problems
by Steve Checkoway 18 Sep '11

18 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Sep 17, 2011, at 15:35 , Jonas Maebe wrote: On 17 Sep 2011, at 21:17, Ingemar Ragnemalm wrote: -- Steve Checkoway _______________________________________________ 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 You are right, that did it for this example! Only one detail: AFAIK the EINTR checks are superfluous in the default setting, since the default behavior is to restart the interrupted call. I'm fairly sure that's not true. The FPC run time library missed several such EINTR checks when I first did the Mac OS X port, and this caused a lot of problems on Mac OS X until I fixed them. These errors hadn't been noticed before because interrupted systems are much less likely to happen on Linux than on Mac OS X (or they were at least back then, around 2004). Maybe I'm misreading the sigaction(2) man page, but it seems to say that the only system calls that might return EINTR when interrupted by a signal are "open(2), read(2), write(2), sendto(2), recvfrom(2), sendmsg(2), and recvmsg(2) on a communications channel or slow device (such as a terminal, but not a regular file) and during a wait(2) or ioctl(2)." (However, the man page says "including" rather than "are" so it's possible it really is just giving a partial list.) Of course, the close(2) man page includes EINTR. I think the only way those would not be restarted is if a signal handler for the signal were installed via sigaction(2) without using the SA_RESTART flag (signal(3) uses the SA_RESTART flag) or the behavior is changed via siginterrupt(3). That is, from what I've read restart is the default behavior on Mac OS X. I suppose one could check the xnu source to be sure. smime.p7s

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Re: Still more pty problems
by Jonas Maebe 17 Sep '11

17 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 17 Sep 2011, at 21:17, Ingemar Ragnemalm wrote: > You are right, that did it for this example! Only one detail: AFAIK the EINTR checks are superfluous in the default setting, since the default behavior is to restart the interrupted call. I'm fairly sure that's not true. The FPC run time library missed several such EINTR checks when I first did the Mac OS X port, and this caused a lot of problems on Mac OS X until I fixed them. These errors hadn't been noticed before because interrupted systems are much less likely to happen on Linux than on Mac OS X (or they were at least back then, around 2004). Jonas _______________________________________________ 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: Still more pty problems
by Ingemar Ragnemalm 17 Sep '11

17 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Thunderbird 2.0.0.24 (Macintosh/20100228) Jonas Maebe wrote: On 16 Sep 2011, at 22:12, Ingemar Ragnemalm wrote: You also have to reap the child processes. So something like this: void RunTest(int i) { int pty, childpid, res; /Ingemar _______________________________________________ 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… Thanks, but it doesn't explain why it would fail after a pretty exact number of runs. And it still does, with the correction. switch((childpid=forkpty(&pty, NULL, NULL, NULL))) { case -1: // Error printf("pty error after %d\n", i); exit(1); case 0: // Child _exit(0); default: // Parent do { res = close(pty); } while ((res == -1) && (errno == EINTR)); do { res = waitpid(childpid,NULL,0); } while ((res == -1) && (errno == EINTR)); } } You are right, that did it for this example! Only one detail: AFAIK the EINTR checks are superfluous in the default setting, since the default behavior is to restart the interrupted call. That will save some lines of code. That is, granted that this is default on OSX and not only on some other Unix. So if I miss a close, it locks up after about 30 runs since I run out of ptys, and if I miss a waitpid I will run out of child processes since I get too many zombies. I suppose that the limit is 256. This email sent to site_archiver(a)lists.apple.com

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Re: Still more pty problems
by Jonas Maebe 16 Sep '11

16 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 16 Sep 2011, at 22:12, Ingemar Ragnemalm wrote: > Thanks, but it doesn't explain why it would fail after a pretty exact number of runs. And it still does, with the correction. You also have to reap the child processes. So something like this: void RunTest(int i) { int pty, childpid, res; switch((childpid=forkpty(&pty, NULL, NULL, NULL))) { case -1: // Error printf("pty error after %d\n", i); exit(1); case 0: // Child _exit(0); default: // Parent do { res = close(pty); } while ((res == -1) && (errno == EINTR)); do { res = waitpid(childpid,NULL,0); } while ((res == -1) && (errno == EINTR)); } } Jonas _______________________________________________ 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: Still more pty problems
by Ingemar Ragnemalm 16 Sep '11

16 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Thunderbird 2.0.0.24 (Macintosh/20100228) Jonas Maebe <jonas.maebe(a)elis.ugent.be> wrote void RunTest(int i) { int pty; One error here: close can be interrupted, so you need int res; do { res = close(pty); } while ((res == -1) && (errno == EINTR)); /Ingemar _______________________________________________ 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 16 Sep 2011, at 14:49, ingemar(a)ragnemalm.se wrote: switch(forkpty(&pty, NULL, NULL, NULL)) { case -1: // Error printf("pty error after %d\n", i); exit(1); case 0: // Child _exit(0); default: // Parent close(pty); } Jonas Thanks, but it doesn't explain why it would fail after a pretty exact number of runs. And it still does, with the correction. This email sent to site_archiver(a)lists.apple.com

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Re: Still more pty problems
by Jonas Maebe 16 Sep '11

16 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 16 Sep 2011, at 14:49, ingemar(a)ragnemalm.se wrote: void RunTest(int i) { int pty; switch(forkpty(&pty, NULL, NULL, NULL)) { case -1: // Error printf("pty error after %d\n", i); exit(1); case 0: // Child _exit(0); default: // Parent close(pty); } One error here: close can be interrupted, so you need int res; do { res = close(pty); } while ((res == -1) && (errno == EINTR)); Jonas _______________________________________________ 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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Still more pty problems
by ingemar＠ragnemalm.se 16 Sep '11

16 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Importance: Normal User-agent: SquirrelMail/1.4.16 Is there anyone here who knows forking and ptys well? I have been trying to fix my failing ptys for quite some time (like, now and then for a few years), and now I am trying again, and have narrowed it down to a small demo: --- #include <stdio.h> #include <util.h> #include <stdlib.h> #include <unistd.h> void RunTest(int i) { int pty; switch(forkpty(&pty, NULL, NULL, NULL)) { case -1: // Error printf("pty error after %d\n", i); exit(1); case 0: // Child _exit(0); default: // Parent close(pty); } } int main(int argc, char *const argv[]) { int i; for (i = 0; i < 1000; i++) RunTest(i); printf("Successfully ran %i times\n", i); exit(0); } // Ultra-minimal pty demo showing the problem I have with failing pty code. // The program just creates and closes ptys over and over. // This will fail after pretty exactly 232 runs. (I have also seen 231 and 233.) // If I don't close the pty, after 30 (running out of ptys). // So I am running out of something else. What? --- This shows fairly well what I am doing in as few lines as possible, and I wonder what I am doing wrong. There is some kind of resource of which there are only about 232, but it isn't the PTYs themselves. What more is there for me to close? The result of this problem in a full application is, obviously, that after running 232 sub-processes with forkpty, my program will fail. BTW, I am running this under OSX 10.6.7, on a MacBook from 2009 (Core2Duo). /Ingemar _______________________________________________ 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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Fwd: Still having issues with mach_vm_readoverwrite
by evan schoffstall 10 Sep '11

10 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=9UosHM0g8PMPN7JUYga1Prg1oHjhOYfMHhfJ7zwhiJE=; b=FK1RK4d6wdQNQBrf0uyasPEdw6rQk9MNh2xwDoAhSDxsTCJqYTSChe9H98a+4LwO6W N8t6a6gKudRmzMKGBvKkA06qA8T19xHO6zOch1XvXOFlArlw7ij26o297XD5dfYo51xc JytswmXyX3Ys9pEoNsMhcGMZp9Ir4uXho/zDs= Forgot reply to all. My apologies. -- Address 0 returns kReturn KERN_SUCESS. WorldState is 0. Is this right? _______________________________________________ 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: Still having issues with mach_vm_readoverwrite
by comex 10 Sep '11

10 Sep '11

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; bh=VE13DhmuqczVYvp4vBU3MXIKjGaLjNMUZPk0x9AP31U=; b=vO2KS3n5UpWB6SP9gWVMp2a2hUln7+VduXxYG6VAW0dlmRPewkCN+JKBVrZrij2fwa h1SMtGb+5BxNfO2r/JNC9IcGOqoo5DWziuKvMg1C/IWdfo8GBYOFYCnICs0tlTZaNMjw HoabVn6W/2ZkOCLXcT/w755jhJ0/OoLr0NVSc= On Fri, Sep 9, 2011 at 5:53 PM, Evan Schoffstall <evan.schoffstall(a)gmail.com> wrote: > The actual address in question is actually 0x11F4A8D40 > I changed the value to sizeof(…) and noticed that kReturn is actually > returning 1.. > I obtained the address via iHaxGamez, so I know the value is there under > that address. > Is there a fancy process I have to go through to get an iHaxGamez address to > a mach_vm_address_t? Oh, I didn't notice before - instead of (vm_address_t) worldState, you want (mach_vm_address_t) &worldState - the code you posted would try to read to address 0. _______________________________________________ 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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