October 2006 - Darwin-dev - lists.apple.com

Re: per user agents/login items
by Stéphane Sudre 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On mardi, octobre 10, 2006, at 11:02 PM, Philip Lukidis wrote: _______________________________________________ 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… Hello. I have a daemon which provides access to a certain device. However, the device needs to have text displayed on its LCD which fits the current locale. Unfortunately, I don't know of a way to query the current user's locale in a daemon (assuming there is a current user), as it runs under the root user. Any solution must work in 10.3 and 10.4... Therefore, is there a way to: a) Let the daemon be notified of user logon, and query the locale of that user? b) Split user dependent functionality out of the daemon and run it as a per user item. However, the daemon would need to communicate with this item and get the locale, and I don't know how to create a per user startupitem. c) Could the daemon be notified of user login, and spawn a helper app in that user session which would return the locale? 1. When no user is logged in, you can probably assume that the system language is OK, you can find this information in the /var/log/CDIS.custom file. 2. You can be informed of user login/logout via the SystemConfiguration Framework. Just take in count that Fast User Switching can pretend there is a user logged in while it's only the login window being displayed. 3. You can spawn a helper app and communicate with your daemon using Message Ports, sockets, pipe, etc... I'm a big fan of CFMessagePort but YMMV. 4. If you use a helper app, you should probablynot look for the locale but use the CoreFoundation API to access localized strings. This email sent to site_archiver(a)lists.apple.com

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per user agents/login items
by Philip Lukidis 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thread-index: Acbsr2ULQKrL6qKkRl6iSzT2e4AyKw== Thread-topic: per user agents/login items Hello. I have a daemon which provides access to a certain device. However, the device needs to have text displayed on its LCD which fits the current locale. Unfortunately, I don't know of a way to query the current user's locale in a daemon (assuming there is a current user), as it runs under the root user. Any solution must work in 10.3 and 10.4... Therefore, is there a way to: a) Let the daemon be notified of user logon, and query the locale of that user? b) Split user dependent functionality out of the daemon and run it as a per user item. However, the daemon would need to communicate with this item and get the locale, and I don't know how to create a per user startupitem. c) Could the daemon be notified of user login, and spawn a helper app in that user session which would return the locale? I have read that LaunchAgents are broken under 10.4 and so they are not viable for me. If anyone has any ideas on the matter, I would appreciate a pointer. thank you, Philip Lukidis _______________________________________________ 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: MacOS X equivalent of swapon/swapoff?
by Markus Hitter 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Am 10.10.2006 um 20:08 schrieb Alison Cassidy: Markus - - - - - - - - - - - - - - - - - - - Dipl. Ing. Markus Hitter http://www.jump-ing.de/ _______________________________________________ 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'll never quiet *all* disk activity; all I can hope for is to minimize it somehow. In case you have some tight realtime requirements, did you check the usual procedures for audio/video handling? This email sent to site_archiver(a)lists.apple.com

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Re: MacOS X equivalent of swapon/swapoff?
by Graham J Lee 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 10 Oct 2006, at 19:19, John Francini wrote: a) Make a copy of the original /etc/rc as a backup b) comment out the call to dynamic_pager c) reboot. Or run the program completely in single user ;-) _______________________________________________ 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… Another option is to move the pager from /var/vm to a statically- mounted FS on a different controller, if that provides enough of a separation between your interested and unfortunately coincident disk activities. -- Graham J Lee http://www.thaesofereode.info/ This email sent to site_archiver(a)lists.apple.com

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Re: MacOS X equivalent of swapon/swapoff?
by John Francini 10 Oct '06

10 Oct '06

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: MacOS X equivalent of swapon/swapoff?
by Alison Cassidy 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Indeed! :) Thanks again, -- Allie _______________________________________________ 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 Oct 10, 2006, at 10:51 AM, Justin C. Walker wrote: On Oct 10, 2006, at 10:34 , Alison Cassidy wrote: Fair point. However, I'm assuming the kernel memory management will deal accordingly in some sane manner. See; http:// unixhelp.ed.ac.uk/CGI/man-cgi?swapoff+2 Mac OS X is not Linux :-} In any case, from that man page, I don't see how you can do both of "quiet all disk activity" and avoid the problem I mention above (which really isn't specific to your process; modern OSs have a lot of processes that can fire at any time to handle the exigencies of the moment; they need to be able to run, or the system crumbles). Right. I'll never quiet *all* disk activity; all I can hope for is to minimize it somehow. You could, as mentioned earlier in this thread, avoid enabling the paging daemon. With sufficient memory, you could run a full system, but things may start failing in strange ways without the elasticity provided by a backing store. In case you haven't looked in depth at the Mac OS X VM system, it's all handled by the paging daemon. There is no path to disk (for this purpose) within the kernel. Right (and thanks John and Graham for the info there). I'd considered messing about with dynamic_pager but wouldn't like to modify the boot args nor kill it outright for very obvious reasons. I need to look into the workings of the paging daemon some more ... This email sent to site_archiver(a)lists.apple.com

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Re: StartupItem & Mac OS X 10.4 & later
by Dave Zarzycki 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Oct 10, 2006, at 10:52 AM, Stephane wrote: On Oct 10, 2006, at 7:04 PM, Dave Zarzycki wrote: On Oct 10, 2006, at 9:27 AM, Stephane Sudre wrote: Actually, my main dependencies are: - System Configuration is available - KPI Kernel Extensions can attach IP, Socket, Interface Filters. davez _______________________________________________ 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… [...] - there is no dependency mechanism such as "only start when network is initialized". The problem is that the network is never done initializing on a modern operating system. It can and will change at runtime. If you fix your daemon to deal with that, then the so-called "dependancy" evaporates. We have found this to be true of all dependencies. They're just declarations of assumptions about how the world won't change on them. Once you fix software to deal with reality, then the need for "dependencies" goes away. Maybe these are already available when launchd runs. As far as you're concerned, those are condoned assumptions that are handled implicitly as you make regular API calls. This email sent to site_archiver(a)lists.apple.com

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Re: StartupItem & Mac OS X 10.4 & later
by Dave Zarzycki 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Oct 10, 2006, at 10:04 AM, Dave Zarzycki wrote: Not to leave you in the dark, here is a link: http://developer.apple.com/documentation/Networking/Conceptual/SystemConfig… davez _______________________________________________ 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… - there is no dependency mechanism such as "only start when network is initialized". The problem is that the network is never done initializing on a modern operating system. It can and will change at runtime. If you fix your daemon to deal with that, then the so-called "dependancy" evaporates. We have found this to be true of all dependencies. They're just declarations of assumptions about how the world won't change on them. Once you fix software to deal with reality, then the need for "dependencies" goes away. This email sent to site_archiver(a)lists.apple.com

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Re: StartupItem & Mac OS X 10.4 & later
by Stephane 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Oct 10, 2006, at 7:04 PM, Dave Zarzycki wrote: On Oct 10, 2006, at 9:27 AM, Stephane Sudre wrote: Actually, my main dependencies are: - System Configuration is available - KPI Kernel Extensions can attach IP, Socket, Interface Filters. Maybe these are already available when launchd runs. _______________________________________________ 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… [...] - there is no dependency mechanism such as "only start when network is initialized". The problem is that the network is never done initializing on a modern operating system. It can and will change at runtime. If you fix your daemon to deal with that, then the so-called "dependancy" evaporates. We have found this to be true of all dependencies. They're just declarations of assumptions about how the world won't change on them. Once you fix software to deal with reality, then the need for "dependencies" goes away. This email sent to site_archiver(a)lists.apple.com

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Re: MacOS X equivalent of swapon/swapoff?
by Justin C. Walker 10 Oct '06

10 Oct '06

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Oct 10, 2006, at 10:34 , Alison Cassidy wrote: On Oct 10, 2006, at 10:24 AM, Justin C. Walker wrote: On Oct 10, 2006, at 10:10 , Alison Cassidy wrote: Mac OS X is not Linux :-} How do you avoid this problem in Linux? Justin -- Justin C. Walker, Curmudgeon-At-Large Institute for the Absorption of Federal Funds -------- Some people have a mental horizon of radius zero, and call it their point of view. -- David Hilbert -------- _______________________________________________ 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… Does anyone know if there is a programmatic way of switching VM on and off, similar to the way Linux does it? I've good reason to do this (honest!) and need some way to disable VM for the duration of running my app or at the least, ensure it doesn't flush to disk at the wrong moment. AFAIK, no OS that supports VM has such a feature. How would you deal, within your app, with this problem: you are running, you "turn off VM", the next instruction to be executed in your app lies at the start of a page that, oops, is paged out? Fair point. However, I'm assuming the kernel memory management will deal accordingly in some sane manner. See; http://unixhelp.ed.ac.uk/ CGI/man-cgi?swapoff+2 In any case, from that man page, I don't see how you can do both of "quiet all disk activity" and avoid the problem I mention above (which really isn't specific to your process; modern OSs have a lot of processes that can fire at any time to handle the exigencies of the moment; they need to be able to run, or the system crumbles). There may be more reasonable ways to solve your problem. Can you be more specific about what you are trying to do? I'm trying to quiet disk activity. If I could suspend the OS File Manager temporarily, I would do so :) Right now, I'm even running a separate pthread to sync() on a very regular basis to ensure that the kernel doesn't build up too many dirty blocks which it would otherwise flush in a flurry of disk activity. I'm doing some very strange things indeed! You could, as mentioned earlier in this thread, avoid enabling the paging daemon. With sufficient memory, you could run a full system, but things may start failing in strange ways without the elasticity provided by a backing store. In case you haven't looked in depth at the Mac OS X VM system, it's all handled by the paging daemon. There is no path to disk (for this purpose) within the kernel. This email sent to site_archiver(a)lists.apple.com

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