January 2008 - Darwin-dev - lists.apple.com

Re: Cancel Sleep
by Uli Kusterer 30 Jan '08

30 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Cheers, -- M. Uli Kusterer "The Witnesses of TeachText are everywhere..." http://www.zathras.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… On 31.12.2007, at 19:53, Michael Smith wrote: If the user does not want the system to sleep, the user *should*not*tell*the*system*to*sleep*. Users make mistakes. One of Jef Raskin's basic ideas in the design of the Macintosh was "forgiveness", to let the user undo dangerous actions, or to warn them before they do them. Neither is possible if the user is about to lose data because an application is interrupted in communication with the network or another external entity. It might be reasonable to ask Apple for a preference which dissociates closing the lid from the act of putting the system to sleep, although I would strongly expect that this would be refused for several sensible reasons, but it is *not* reasonable to ask for a programmatic way to subvert the user's intent in the fashion the OP desires. I've worked on a product which was essentially a background program that was doing live device communication. Often, users chose "Sleep" from the menu bar and accidentally interrupted the communication, causing the device to suddenly stop and files to be truncated prematurely. It would really be useful if there was a way to delay sleep a little and pop up a warning dialog or warn the user via speech synthesis to quickly re-open the device (or type a key or otherwise cancel the sleep in progress) before the system cuts off connection to the device. This email sent to site_archiver(a)lists.apple.com

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Re: screen clobbers PATH
by David Mackler 30 Jan '08

30 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com ----- Original Message ---- > From: Martin Costabel <costabel(a)wanadoo.fr> > To: darwin-dev(a)lists.apple.com > Sent: Tuesday, January 29, 2008 11:23:19 PM > Subject: screen clobbers PATH > > I have asked this elsewhere and got no response, even spent time > studying the source and got no response either ;-) > > Here is the problem: > > On Leopard, in the shell started by /usr/bin/screen, the PATH variable > is set to > > /usr/bin:/bin:/usr/sbin:/sbin > > All other environment variables, for example MANPATH or CLASSPATH, are > copied from the environment of the shell from which screen is started. > Only PATH is crippled to this minimalist value. > > This did not happen in Tiger, and it does not happen with other builds > of screen, for example from Fink. > > Does anyone have an explanation for this annoying behavior, or, more > importantly, a fix? No fix, but neither do I see the problem: (from my screen session) [david@FourSpeed:~ 2006]$ echo $PATH /sw/bin:/sw/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/X11R6/bin What do you have in your .screenrc? How are you starting screen? Here is my .screenrc: [david@FourSpeed:~ 2007]$ cat .screenrc # Turn off the startup message. startup_message off # increase default scrollback buffer and use UTF-8 defscrollback 1000 defutf8 on # display activity message by default #defmonitor on # Do not use xterms alternate window buffer (won't add lines to scrollback bfr) #termcapinfo xterm|xterms|xs|xterm-color ti=\E7\E[?47l # Set the caption to the active windows caption always "%l: %-Lw%{= BW}%50>%n%f* %t%{-}%+Lw%<" # New screens for various fixed processes screen -t console 0 tail -n 30 -F /var/log/system.log screen -t links 1 /sw/bin/links $HOME/.links/startpage.html # Create a window and use the default shell screen $SHELL # Display the first window select 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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screen clobbers PATH
by Martin Costabel 30 Jan '08

30 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com User-agent: Mozilla Thunderbird 1.0.2 (Macintosh/20050317) Here is the problem: /usr/bin:/bin:/usr/sbin:/sbin -- Martin _______________________________________________ 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 asked this elsewhere and got no response, even spent time studying the source and got no response either ;-) On Leopard, in the shell started by /usr/bin/screen, the PATH variable is set to All other environment variables, for example MANPATH or CLASSPATH, are copied from the environment of the shell from which screen is started. Only PATH is crippled to this minimalist value. This did not happen in Tiger, and it does not happen with other builds of screen, for example from Fink. Does anyone have an explanation for this annoying behavior, or, more importantly, a fix? This email sent to site_archiver(a)lists.apple.com

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Re: Program not exiting
by Dave Zarzycki 30 Jan '08

30 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Andre, Sorry, davez On Jan 29, 2008, at 4:19 PM, Andre-John Mas wrote: Hi, lsof yields no associated files with the process. Andre _______________________________________________ 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/zarzycki%40apple.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… Processes stuck in the 'E' state require a kernel debugger investigate further. I am working with a project which does serial port communication. I opened the serial port and attempted to close it. Since then my application has stayed in the exiting state, for the past 3 days. Attempting to do a 'kill -9' on it has no success. The entry from ps is: ajmas 8833 0.0 0.0 0 0 ?? E Wed10pm 0:00.00 (java) Is there any way of establishing what could be preventing the application from exiting? I am using MacOS X 10.5.1. This email sent to zarzycki(a)apple.com This email sent to site_archiver(a)lists.apple.com

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Program not exiting
by Andre-John Mas 30 Jan '08

30 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi, lsof yields no associated files with the process. Andre _______________________________________________ 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 am working with a project which does serial port communication. I opened the serial port and attempted to close it. Since then my application has stayed in the exiting state, for the past 3 days. Attempting to do a 'kill -9' on it has no success. The entry from ps is: ajmas 8833 0.0 0.0 0 0 ?? E Wed10pm 0:00.00 (java) Is there any way of establishing what could be preventing the application from exiting? I am using MacOS X 10.5.1. This email sent to site_archiver(a)lists.apple.com

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Re: Running a time consuming background process
by Terry Lambert 29 Jan '08

29 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com For example: cat /tmp/foo | my_batch_program How would you reopen descriptor 0 at the right place? -- Terry _______________________________________________ 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 Jan 27, 2008, at 10:56 AM, Tommy Nordgren wrote: I need to run a custom program that I expect to need several weeks of (wall clock) time to complete. How can I set up and run so that I can save state on any signal, and having my program automatically resumed on start up, with as little extra work as possibly when resuming. My program is a pure batch job, by the way. It's called checkpoint/restart, and you can do it in user space using an appropriate third party library (such as "Libtckpt"). There are bunches of other options, but that the first one that comes up in google, and it's one I played with once upon a time. This is not a service offered by the OS, since it has no idea what passwords you used for all your network connections, network shares, or how to reopen some types of decriptors (e.g. those to named pipes in /var/run or /tmp, which no longer exist, socket connections to servers that are now down or were over a VPN that you didn't start back up, firewire disks that have since been unplugged from the machine, etc.). This is a case where you are up against the halting problem, and it's better to use a library and constrain your applications behaviour to only those things that the library knows how to restart, rather than trying to solve the problem generally for all possible applications. This email sent to site_archiver(a)lists.apple.com

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Re: [Fwd: Re: execv bug???]
by Terry Lambert 29 Jan '08

29 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com See the vfork man page: Peter is 100% correct here. You pretty much have three choices here: (2) Switch to using fork() instead (3) Switch to using posix_spawn() -- Terry _______________________________________________ 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 Jan 27, 2008, at 11:56 AM, Peter Seebach wrote: In message <479CD1DB.4030504(a)yahoo.com>, Steve writes: So, are you suggesting then it could well be a bug with Leopard (it works fine on Tiger and, it works fine as coded by simply removing the v from vfork)? Obviously, the simple solution on Leopard for now is to use fork. I shall proceed to make a small test program and submit to Apple then. I wouldn't consider it a significant bug; vfork is deprecated, having been a performance hack to improve performance on the VAX. The existence of modern systems with copy-on-write semantics makes it a waste of time to try to make things work with vfork; further, I wouldn't necessarily expect either process to be stable after calling vfork and then doing anything other than exec* and exit -- there's nothing I know of stating that chdir() calls can't have side-effects that include modification of the caller's address space in some way, and you should never call anything that modifies the caller's address space from the child side of a vfork. [EINVAL] A system call other than _exit() or execve() (or libc functions that make no system calls other than those) is called following calling a vfork() call. chdir() is a syscall. It is an error to call chdir() inside the child of a vfork. When you vfork(), you "borrow" the parent process Mach task, Mach thread, and BSD uthread, creating your own BSD process structure. Any system call subsequent to a vfork() and prior to an execve() or _exit(), and which operates on anything other than the BSD process structure, will modify the state of the parent process, rather than that of the child process. If you are lucky, then the child process inherits the changed values from the parent process, and if you are very, very lucky, the parent process doesn't mind this twiddling happening. Many OSs will in fact error out all system calls, other than execve() and _exit() subsequent to a vfork(), and are correct to do so; however, POSIX states that the behaviour is "undefined", and permits the return of an EINVAL error - but does not require it. I made a number of egregious system calls return EINVAL (those that would modify credential and process group information), but didn't disable everything, since it would have strongly damaged binary compatibiliy. Instead, it's "deprecated", which means you should not depend on it for newly compiled code. (1) Save the current directory before the vfork(), change the current directory of the main process to the one you want the child to have, call vfork(), and when the parent gets back from the call, put the parents directory back to what it was Plan your code as if you expect vfork() to get more strict about the calls that it allows between it and execve()/_exit(); even if nothing changes in MacOS X, your code will be more portable. This email sent to site_archiver(a)lists.apple.com

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Re: Darwin 8.11 and 9.1 Source
by William Siegrist 29 Jan '08

29 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thanks -Bill On Jan 28, 2008, at 1:13 PM, Rosyna wrote: On Jan 26, 2008, at 4:47 PM, William Siegrist wrote: --- Sincerely, Rosyna Keller Technical Support/Carbon troll/Always needs a hug Unsanity: Unsane Tools for Insanely Great People It's either this, or imagining Phil Schiller in a thong. ---- William Siegrist Software Support Engineer Mac OS Forge http://macosforge.org/ wsiegrist(a)apple.com 408 862 7337 _______________________________________________ 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 I'm working on tracking down the missing sources, I apologize for not making that clear in my previous email. If you find something missing that hasnt been mentioned before, and want to make sure I know about it, you can email this list or myself directly. But I'll be going over all the listings and looking for broken links in any case. Is it? Still not CF, CFNetwork, or Objective-C code for 10.5.1. And the dyld code for 10.4.11 is missing (http://www.opensource.apple.com/darwinsource/10.4.11.ppc/dyld-46.16/ ) and it's something I really need.... The CF source is also missing for 10.4.11. The Darwin team is pleased to announce the availability of the source code for Darwin 8.11 and 9.1. These sources correspond to Mac OS X 10.4.11 and 10.5.1 respectively, for both PowerPC- and Intel-based Macintoshes. smime.p7s

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Re: [Fwd: Re: execv bug???]
by Ryan McGann 29 Jan '08

29 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Well, if performance really mattered, then multiple processes wouldn't be used. Debating fork() versus vfork() is like debating whether you can run faster with 10 or 20 pounds attached to your ankles. Either way, you're going to run slower than the guy with no weights attached to his ankles. I'm calling the (default, system-supplied) assembler from the compiler once per compiled source file. I think that is a perfectly normal use- case and not an example of using the wrong tools/api's for the job (afaik, the assembler does not support batch processing). Ryan _______________________________________________ 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'd say not considering that's how Xcode does things as well. And not to rag on Xcode, but when compiling a C++ application with 500+ files in it for 4 different architectures (ppc[64], x_86[64]), Xcode spawns a couple (thousand) processes. So unless Xcode is going to be rewritten so that it doesn't spawn gcc and ld, I'd say performance of fork does matter :-) This email sent to site_archiver(a)lists.apple.com

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Re: [Fwd: Re: execv bug???]
by Jonas Maebe 28 Jan '08

28 Jan '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 28 Jan 2008, at 17:30, Jonas Maebe wrote: 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… c) I concluded from this that that I should libc instead as a system interface, and that it would be just as stable (if not more so) since Apple is a commercial company The fact that even this interface may not remain backward compatible is disappointing however. When I first learned about the concept of frameworks, I (naively) assumed this meant that breaking backwards library compatibility would no longer be required, since you could just bump the compatibility version so all older programs could transparently keep using the older version of the framework. Obviously, for something like libSystem this is not a solution "for free" since you'd still have to keep patching the old version to keep running on the new syscall interfaces if older syscalls are removed/changed. Actually, it seems I misread the comments about vfork being deprecated, as the man page states: This system call will be eliminated when proper system sharing mechanisms are implemented. Users should not depend on the memory sharing semantics of vfork as it will, in that case, be made synonymous to fork. So as long the symbol remains exported from libSystem (synonymous to fork at some point or not), it doesn't matter to me (from a backwards binary compatibility standpoint). This email sent to site_archiver(a)lists.apple.com

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