February 2007 - Darwin-dev - lists.apple.com

LACP implementation in MAC OS X 10.4-dlil replacement
by Anees Alappat 13 Feb '07

13 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:mime-version:content-type; b=G5uPkPyNfwRVoylUcWvH95mYqGHzs2cKBFkvJcty0bh0Hm+5yVdfDzBUavLADG27GyGsjMznJNuBIwfmjf140vRGUki1N/WcWyF6A+cdaa0jjt4IxGhYNDdeygoDZy2mwjxLkxbIZaVyh9iXuGvTZGtbsihvNBq08nWnJUHgpt8= _______________________________________________ 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

1 0

sem_timedwait
by Heidi Zhou 13 Feb '07

13 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:Date:From:Subject:To:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-ID; b=kgpKnl13o2mJP4WD3ZTKvhyojlLuLIE90btJ8gDVPXoT6rYAYclOzmnYHe7QRsnLaccxn20yKBFhypzpEjjDGclbNGgiSqx7I0/y4F4AHSbi9S0N4j3c8pizo2a7jHwFCt+Z756vEyyqSVS54nvxZFBZNzmYpNvPdDYnJaf1gP0=; Hello! I am working on a project that needs to use the Posix function sem_timedwait so that a thread waits on a semaphore until it either gets the semaphore or timeout. However, it seems that sem_timedwait is not supported on Darwin. Am I right? If yes, any suggestion on a work around? Thank you. Heidi ____________________________________________________________________________________ Have a burning question? Go to www.Answers.yahoo.com and get answers from real people who know. _______________________________________________ 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

1 0

Re: argh re: header versions
by Daniel J. Luke 08 Feb '07

08 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com The right place is probably Apple's bugreporter. Edit the configure.in Change AC_MSG_ERROR([Your OpenSSL headers do not match your library.]) to AC_MSG_WARN([Your OpenSSL headers do not match your library.]) then regen the configure script and things will probably be OK. -- Daniel J. Luke +========================================================+ | *---------------- dluke(a)geeklair.net ----------------* | | *-------------- http://www.geeklair.net -------------* | +========================================================+ | Opinions expressed are mine and do not necessarily | | reflect the opinions of my employer. | +======================================================== _______________________________________________ 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 On Feb 7, 2007, at 7:11 PM, Peter Bartoli wrote: Sorry to vent here, especially if this is the wrong place, but when you guys issue binary updates to libraries via OS X, could you *please, please pretty please* make sure to update the associated headers? This sucks. checking OpenSSL header version... 90709f (OpenSSL 0.9.7i 14 Oct 2005) checking OpenSSL library version... 9070cf (OpenSSL 0.9.7l 28 Sep 2006) checking whether OpenSSL's headers match the library... no configure: error: Your OpenSSL headers do not match your library. or use MacPorts/fink/openssl source to get matching openssl library and headers. PGP.sig

1 0

argh re: header versions
by Peter Bartoli 08 Feb '07

08 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com checking OpenSSL header version... 90709f (OpenSSL 0.9.7i 14 Oct 2005) checking OpenSSL library version... 9070cf (OpenSSL 0.9.7l 28 Sep 2006) checking whether OpenSSL's headers match the library... no configure: error: Your OpenSSL headers do not match your library. -peter _______________________________________________ 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 to vent here, especially if this is the wrong place, but when you guys issue binary updates to libraries via OS X, could you *please, please pretty please* make sure to update the associated headers? This sucks. This email sent to site_archiver(a)lists.apple.com

1 0

Re: Reducing interruption latency for feedback-loop
by Michael Smith 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Date: Wed, 7 Feb 2007 09:58:18 -0800 From: "CJ Bell" <siegebell(a)gmail.com> Subject: Reducing interruption latency for feedback-loop To: darwin-dev(a)lists.apple.com Message-ID: <64e20a610702070958r3c7624cjdb4ad1502f05ee17(a)mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed I'm trying to get a feedback-loop for a digital-analog converter running at 40 kHz (or faster). Ideally, I would like to respond to each sample as it comes and not let any back up. This is essentially what I have so far: thread_priority_set(...) start while(running) { if(sample is ready) { read/write usleep(0); } } stop I have been able get it to run for 24 sec with only 100 to 200 interruptions that, each time, cause roughly 4 samples to back up -- on a 1.17 GHz dual-core G4, using a 3rd-party driver which communicates via PCI. Since the device-manufacturer doesn't yet provide PCI Express cards, I am unable to upgrade computers at this time. Using a multi-core computer, can I tell the scheduler to ensure that the thread runs uninterrupted (well, with interruptions limited to 30 or 40 usec in latency) on a CPU at all times? No. Yes. = 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… I'm a little unclear as to what you're describing here, and particularly what you mean by "not let any back up". This implies that you are running in userspace, and since there are no hard realtime guarantees available to you, you must be prepared to tolerate delays of tens or hundreds of milliseconds. Any suggestions on how to reduce the interruption latency? Do your work at primary interrupt time, in the device driver's interrupt filter method. Is it necessary to work in the kernel to achieve what I'm looking for? Can I increase the granularity of usleep()? I'm not sure what you mean by "increase the granularity". As has been pointed out, usleep() is typically as precise and reliable as it can be on a given system. I don't think that's really relevant here though. This email sent to site_archiver(a)lists.apple.com

1 0

Re: Reducing interruption latency for feedback-loop
by CJ Bell 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=p76TTqGi/IiIW6bwuIwm4s8pxsk0QvkuJ5W+bTDegf/Mq92PzSwVmOYVg4GqN771Q2QRpQu6+2a8H/5g9d5oVpX2fLhFtVhZrzucCiSiXzWpygICcPGuEgU632xjRyFtS6kGiEDGMHUIwc4U50FDkv9PcH/b2NrOvdh0bo0vLgs= usleep(0) calls through to nanosleep according to the man page, and nanosleep will just perform a spinning loop if you ask it to wait shorter than X ms (I don't know the exact cut-off). That's not what you want, I think. If you just want to give up the current time slice, call pthread_yield_np() (or sched_yield() from sched.h, since the pthread variant just calls through to that on Mac OS X) instead. Thanks! I was calling usleep(0) so that I wouldn't lose thread-priority -- it made a huge difference. -CJ _______________________________________________ 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

1 0

Re: how to get the serviceID belongs to airport
by Allan Nathanson 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com How about something like : prefs = SCPreferencesCreate(NULL, CFSTR("your app"), NULL); set = SCNetworkSetCopyCurrent(prefs); services = SCNetworkSetCopyServices(set); for (i = 0; i < CFArrayGetCount(services); i++) { service = CFArrayGetValueAtIndex(services, i); interface = SCNetworkServiceGetInterface(service); interfaceType = SCNetworkInterfaceGetInterfaceType(interface); if (CFEqual(interfaceType, kSCNetworkInterfaceTypeIEEE80211)) { serviceID = SCNetworkServiceGetServiceID(service); CFRetain(serviceID); // release "later" break; } } CFRelease(services); CFRelease(set); CFRelease(prefs); dict = SCDynamicStoreCopyDHCPInfo(store, serviceID); CFRelease(serviceID); ... and, of course, you'd add the appropriate error checks :-) - Allan On Feb 6, 2007, at 8:46 PM, Cotton Chen wrote: -- Cotton Chen _______________________________________________ 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… Hi all, Recently I'd like to get the dhcp server's ip address who gives the ip to my airport. I used the APIs SCDynamicStoreCopyDHCPInfo, and DHCPInfoGetOptionData to accomplish my purpose. But, I cand only pass the NULL value as the serviceID to SCDynamicStoreCopyDHCPInfo because I don't know how to get the serviceID that belongs to airport. I also used scutil to get the informations about dhcp, I got the following of what I want. with ethernet cable connected: subKey [47] = State:/Network/Service/0/DHCP subKey [48] = State:/Network/Service/0/DNS subKey [49] = State:/Network/Service/0/IPv4 subKey [50] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/DHCP subKey [51] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/DNS subKey [52] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/IPv4 without ethernet cable connected: subKey [50] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/DHCP subKey [51] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/DNS subKey [52] = State:/Network/Service/ 606C990F-4091-4AC1-807F-86CC64EB7898/IPv4 as I passed the null value as serviceID to SCDynamicStoreCopyDHCPInfo without ethernet cable connected and turn on the airport interface, I got the correct dhcp server's ip because system had no choice to return me the one belongs to airport. But after I connected the ethernet cable on my computer, I always got the one that belongs to the ethernet interface. My question is, how to get the serviceID belongs to airport, for example the string "606C990F-4091-4AC1-807F-86CC64EB7898" that listed above. This email sent to site_archiver(a)lists.apple.com

1 0

Re: Reducing interruption latency for feedback-loop
by Jonas Maebe 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 07 Feb 2007, at 18:58, CJ Bell wrote: This is essentially what I have so far: thread_priority_set(...) start while(running) { if(sample is ready) { read/write usleep(0); } } stop 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… usleep(0) calls through to nanosleep according to the man page, and nanosleep will just perform a spinning loop if you ask it to wait shorter than X ms (I don't know the exact cut-off). That's not what you want, I think. If you just want to give up the current time slice, call pthread_yield_np() (or sched_yield() from sched.h, since the pthread variant just calls through to that on Mac OS X) instead. This email sent to site_archiver(a)lists.apple.com

1 0

Reducing interruption latency for feedback-loop
by CJ Bell 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=bKdrNP+1UPDAF05pKio+nS+Rfuu8yav0MCnIVHXsVUifTQjGV24xRVeOwxSQenzpKTTLjV/VWEB97LCxaLnE8Nyn2U06qjpQkyAg+bWs5kOHEf1ENS87/2USMsU391f5evS5rfBcuYZhTPd/sEeNqh3ftoJFg5Ll/WnhAvAyYSE= I'm trying to get a feedback-loop for a digital-analog converter running at 40 kHz (or faster). Ideally, I would like to respond to each sample as it comes and not let any back up. This is essentially what I have so far: thread_priority_set(...) start while(running) { if(sample is ready) { read/write usleep(0); } } stop I have been able get it to run for 24 sec with only 100 to 200 interruptions that, each time, cause roughly 4 samples to back up -- on a 1.17 GHz dual-core G4, using a 3rd-party driver which communicates via PCI. Since the device-manufacturer doesn't yet provide PCI Express cards, I am unable to upgrade computers at this time. Any suggestions on how to reduce the interruption latency? Using a multi-core computer, can I tell the scheduler to ensure that the thread runs uninterrupted (well, with interruptions limited to 30 or 40 usec in latency) on a CPU at all times? Is it necessary to work in the kernel to achieve what I'm looking for? Can I increase the granularity of usleep()? Thanks for your time! -CJ _______________________________________________ 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

1 0

how to get the serviceID belongs to airport
by Cotton Chen 07 Feb '07

07 Feb '07

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:mime-version:content-type; b=HBTqAvRRaTOjJGuYG5xNO6cyDuoI3/klSkBdDBPCCIzkxprAp0JA/ho4jNKvG2njFO5K98sio8+6DtC2WJv5iAdqUbr1NDoR4lDhYpnik3Wgn50CXGrqdnT9dqpQ+Gg6XTaLs4ZZ57m1rjPGDxYF4Axj8ljf2Tu9Actvp5I5ZOM= _______________________________________________ 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

1 0