August 2007 - Darwin-kernel

Re: printf logs are not getting printed properly on system.log
by Jeremy Pereira 24 Aug '07

24 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On 23 Aug 2007, at 20:04, Draichis wrote: Amazing. <sys/systm.h> (printf can be used with this) <sys/buf.h> (buffer cache functions like bread) <sys/dirent.h> (directory entries) <sys/errno.h> (Error numbers) <sys.kernel.h> (kernel special variables) <sys/lock.h> (spinlocks) <sys/malloc.h> (malloc) <sys/queue.h> (queues) <sys/rand.h> (random generation numbers) <sys/systm.h> (bzero, bcopy.. etc) <sys/system.h> (timeout, untimeout) <sys/time.h> (time functions) <sys/types.h> <mach/mach_types.h> (standard type declarations) <sys/ucred.h> (user credentials) <sys/utsname.h> (os and system information) _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… One of the most common problems faced when programming in the kernel is use of “standard” functions—things like printf or bcopy. Many commonly used standard C library functions are implemented in the kernel. In order to use them, however, you need to include the appropriate prototypes, which may be different from the user space prototypes for those functions, and which generally have different names when included from kernel code. In general, any non–I/O Kit header that you can safely include in the kernel is located in xnu/bsd/sys or xnu/osfmk/mach, although there are a few specialized headers in other places like libkern and libsa. Normal headers (those in /usr/include) cannot be used in the kernel (or rather, cannot be used 'properly'). If the standard C function you are trying to use is not in one of the following files, chances are the function is not supported for use within the kernel, and you need to implement your code in another way: For developing kernel extensions, surely it is better to be guided by the header files that are in Kernel.framework in the SDK which are also the ones that should be used - at least they are the ones that XCode uses when it creates a new kext project. This email sent to site_archiver(a)lists.apple.com

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Re: printf logs are not getting printed properly on system.log
by Boris Remizov 24 Aug '07

24 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=O6tuXvjd6QWhduj61jDwgxWMMjWdCYhubhG1ge5BGDd6XgZ+NJYW55gXSrnKjxQkd+sb5V+MLXitpsw2WJraienWyLIZTigY+K22vPLX1AWwiAxLIb/3A6zyPMH2YV3AHp+hONyz4Pjch4RjXJ1prI5sxOsNgqaHM9AoekPS6nU= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=TAk7BHdiAzyIqmJHnJdbEDJVfY5ZQVIfIug1qMmsb7cwDx6Q6dyPXlkclWqRyQWHb8rGjr7pHKH2GanpYi2Y2o8kTe6hYLzyMrtZHaCRnpnZTLbSsykzIWlN7JqcuiJJ0EL2IgpviO+BtAYiXCR/Ze1Jrn3qD1g3usEel28lSjs= On Aug 23, 2007, at 23:04 , Draichis wrote: On Aug 23, 2007, at 9:14 AM, Jernej Azarija wrote: Hello, printf("foo\n"); printf("bar\n"); Ends up written in system.log as : fobaro (just a banal example). Amazing. <sys/systm.h> (printf can be used with this) <sys/buf.h> (buffer cache functions like bread) <sys/dirent.h> (directory entries) <sys/errno.h> (Error numbers) <sys.kernel.h> (kernel special variables) <sys/lock.h> (spinlocks) <sys/malloc.h> (malloc) <sys/queue.h> (queues) <sys/rand.h> (random generation numbers) <sys/systm.h> (bzero, bcopy.. etc) <sys/system.h> (timeout, untimeout) <sys/time.h> (time functions) <sys/types.h> <mach/mach_types.h> (standard type declarations) <sys/ucred.h> (user credentials) <sys/utsname.h> (os and system information) On 23 Aug 2007, at 06:05, JanakiRam wrote: > Hi ALL, > > I'm newbie to this kernel prorgamming. Please clarify my > following query. > > I'm using printf for logging messages from my kext. One > observation is all my logs are not getting printed when i start my > kext using kextload. Its not consitent , how many logs are going > to get printed every time i load the kext. > > Please help me to solve this. Thanks in Advance. I've seen the same problem. I assumed it was because of overrunning some buffer somewhere i.e. producing too much output for the kernel logging system to cope with. > > > -JanakiRam. --- Draichis draichis(a)gmail.com draichis(a)craplandia.org http://draichis.craplandia.org _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… I have the same problem especially then i make fat tide of logging. The strings may be corrupted or completely missed. I use my log- wrapper that have additional lock and configurable delay inside, this avoid string corruption and many times let me find bugs in multithreaded processing. recommends this technique :) But my dream is to have connection to the syslogd from the kernel... lets do it guys!!! I've encountered this issue too. Specifically, when a lot of calls to printf() have been made, the output looks messy. eg : One of the most common problems faced when programming in the kernel is use of “standard” functions—things like printf or bcopy. Many commonly used standard C library functions are implemented in the kernel. In order to use them, however, you need to include the appropriate prototypes, which may be different from the user space prototypes for those functions, and which generally have different names when included from kernel code. In general, any non–I/O Kit header that you can safely include in the kernel is located in xnu/bsd/sys or xnu/osfmk/mach, although there are a few specialized headers in other places like libkern and libsa. Normal headers (those in /usr/include) cannot be used in the kernel (or rather, cannot be used 'properly'). If the standard C function you are trying to use is not in one of the following files, chances are the function is not supported for use within the kernel, and you need to implement your code in another way: I checked printf() implementation and it seems that loocking *is* handled correctly so I'm really wondering what's the problem behind it. -----Original Message----- From: darwin-kernel-bounces+jernej.azarija=hermes- softlab.com(a)lists.apple.com on behalf of Jeremy Pereira Sent: Thu 8/23/2007 9:35 AM To: JanakiRam Cc: darwin-kernel(a)lists.apple.com Subject: Re: printf logs are not getting printed properly on system.log "I know that fewer people are won over by the written word than by the spoken word and that every great movement on this earth owes its growth to great speakers and not to great writers." This email sent to site_archiver(a)lists.apple.com

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Re: Memory Restriction in Kext
by Boris Remizov 24 Aug '07

24 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=K+TJAdh0QIyJeoNNEngALMd9qefeW5s4z5CV8qqNiDteVSZS07qpc+5ldm77UulbmhQfi9fZVlUENhD8pZg0zA+LEc1bXg5MShcGMrcezt+jP1O9NQRcFm4bSfgRx1s/LRYb9PnQUIUGTjoIq0p5Tgngbcvjr7uTTPfVBplpt7Y= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=g0pJ8we0LrTCKBxAss0E8/gyTiktotFetJIbksEKlIC4naJ3/HUu48sYO+SehUw7chKjlq3cjEmYFWtoTOn9es2UxZUdabUmRMuwrPvAWR4KxgCtPjAkeg5ctwAufDS1pfUgjBvOOUyNqSDYGTuhsCWlt5LCMFsuvdEjIFTOXCI= On Aug 23, 2007, at 22:38 , JanakiRam wrote: Hi ALL, ii) If so , Whats the maximum limit ? Please help me . Thanks in Advance. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… I'm a newbie to the kernel programming. Can any one clarify my following querie(s). i) Is there any restriction imposed on the memory to be allocated inside a KEXT and its related functions . IMOO the new/delete operations do not use such generic memory management as for example IOMalloc, so new/delete have some additional limitations for listed below... If you use IOMalloc, then you restricted to the comparably small limit of about 100 -- 200 Mb (I don't know the actual size of the pool) If you use IOBufferMemoryDescriptor then you limited with 4Gb address space. If you use 10.4 64-bit memory manager/IODMACommand you have full 64-bit addressing. iii) Can i allocate 1MB ( i.e. char [1024][1024] ) memory in generic kext start function ? Yes you may but remember that heavy loading of stack is not a good practice that leeds to the system inconsistency and difficultly tested bugs. -JanakiRam. This email sent to site_archiver(a)lists.apple.com

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Re: Memory Restriction in Kext
by Michael Smith 24 Aug '07

24 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Aug 23, 2007, at 11:38 AM, JanakiRam wrote: There are serveral. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… I'm a newbie to the kernel programming. Can any one clarify my following querie(s). i) Is there any restriction imposed on the memory to be allocated inside a KEXT and its related functions . There are several restrictions. They are all pretty generous; if you hit any of them, you have a serious design problem. ii) If so , Whats the maximum limit ? - Kernel stacks are small. Do not allocate large auto variables. Ever. - Small allocations come from the zone allocator. The zone submap is constrained; the constraint may vary based on the amount of physical memory in the system. It is, fortunately, fairly fast. - Larger allocations come from the kernel map. You are constrained here by both the available kernel virtual space and the physical memory present in the system, since kernel memory is normally wired down. iii) Can i allocate 1MB ( i.e. char [1024][1024] ) memory in generic kext start function ? Yes, although you may want to do this with an IOBufferMemoryDescriptor so that you have the memory pre-wrapped for I/O purposes. As a general rule, however, if you are allocating large amounts of memory in a driver it's because you think that copying into/out of that memory is a good idea. Usually, you'll be wrong about that. You should, wherever possible, pursue designs that avoid copying, intermediate buffers, handoff between threads and other such obscenities. 8) This email sent to site_archiver(a)lists.apple.com

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Re: printf logs are not getting printed properly on system.log
by Draichis 23 Aug '07

23 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-pgp-agent:x-gpgmail-state:x-mailer; b=HqImMPJKijfaOmPXDMNUKSHNuhL9fx0CRhuA62rZEsV3eWkojTlvDUUrOcGFFLMhqX33HqtcOL+UQOvG8r68C3JrkKuMFouO23vt7IL21nXES1+DkCNLHUAtkC6A9AROLMnTBMrkReQOZ6y4jRKvv5SVYQmkdwiDoO8CnEwqbUg= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-pgp-agent:x-gpgmail-state:x-mailer; b=JRd3Hos6VGWufupfGGec0ytdzE3qvVQCbv03mIaTHvvJLvW718z2RHFcL6ymk/WZWuvKOb8dkgh8/A+RmiqXD9yPgaPMvsj7nBsv/sOqvaQtCoN4EzvSyAtNEF0E/chG+1dTqoCPuee31CRZtKY7nNOTmOPRnk+Basti7z9S99w= On Aug 23, 2007, at 9:14 AM, Jernej Azarija wrote: Hello, printf("foo\n"); printf("bar\n"); Ends up written in system.log as : fobaro (just a banal example). Amazing. <sys/systm.h> (printf can be used with this) <sys/buf.h> (buffer cache functions like bread) <sys/dirent.h> (directory entries) <sys/errno.h> (Error numbers) <sys.kernel.h> (kernel special variables) <sys/lock.h> (spinlocks) <sys/malloc.h> (malloc) <sys/queue.h> (queues) <sys/rand.h> (random generation numbers) <sys/systm.h> (bzero, bcopy.. etc) <sys/system.h> (timeout, untimeout) <sys/time.h> (time functions) <sys/types.h> <mach/mach_types.h> (standard type declarations) <sys/ucred.h> (user credentials) <sys/utsname.h> (os and system information) On 23 Aug 2007, at 06:05, JanakiRam wrote: > Hi ALL, > > I'm newbie to this kernel prorgamming. Please clarify my > following query. > > I'm using printf for logging messages from my kext. One > observation is all my logs are not getting printed when i start my > kext using kextload. Its not consitent , how many logs are going > to get printed every time i load the kext. > > Please help me to solve this. Thanks in Advance. I've seen the same problem. I assumed it was because of overrunning some buffer somewhere i.e. producing too much output for the kernel logging system to cope with. > > > -JanakiRam. --- Draichis draichis(a)gmail.com draichis(a)craplandia.org http://draichis.craplandia.org _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com I've encountered this issue too. Specifically, when a lot of calls to printf() have been made, the output looks messy. eg : One of the most common problems faced when programming in the kernel is use of “standard” functions—things like printf or bcopy. Many commonly used standard C library functions are implemented in the kernel. In order to use them, however, you need to include the appropriate prototypes, which may be different from the user space prototypes for those functions, and which generally have different names when included from kernel code. In general, any non–I/O Kit header that you can safely include in the kernel is located in xnu/bsd/sys or xnu/osfmk/mach, although there are a few specialized headers in other places like libkern and libsa. Normal headers (those in /usr/include) cannot be used in the kernel (or rather, cannot be used 'properly'). If the standard C function you are trying to use is not in one of the following files, chances are the function is not supported for use within the kernel, and you need to implement your code in another way: I checked printf() implementation and it seems that loocking *is* handled correctly so I'm really wondering what's the problem behind it. -----Original Message----- From: darwin-kernel-bounces+jernej.azarija=hermes- softlab.com(a)lists.apple.com on behalf of Jeremy Pereira Sent: Thu 8/23/2007 9:35 AM To: JanakiRam Cc: darwin-kernel(a)lists.apple.com Subject: Re: printf logs are not getting printed properly on system.log "I know that fewer people are won over by the written word than by the spoken word and that every great movement on this earth owes its growth to great speakers and not to great writers." PGP.sig

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Re: printf logs are not getting printed properly on system.log
by Herb Petschauer 23 Aug '07

23 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=udJf9dM0FQxljPfJ3LprMc/B+EQamwqrQktPSErqNntMpNneZjqYU/sh1/OL3GVyVKbaEXjZ6AWf8IPtI1nH2kp+2H3GqGhi1kaqet3qXa1YMVJYId7Js9mQsTw622ip9GuhuKB3x6ntFzUlzcbMYvmmjsU7nXjcn1u0IpcGiGg= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=DOXvffDgkYKIEfRaIeYkNGsPcIbF2rZLy9Q/lGUihNxxR5083OmLgurU3mBPu3KVox8mxySPyq1H4dXz+Yi5RW03DlXQadaVpXI/JOhX7zK47tCMsY1fdUegYIdwautXfvZ8FA5p8Cudz8GxzNQse/2ZEui+ux6a98VFyjMGMTU= Search the archives for "Firewire kprintf" On 23/08/07, Draichis <draichis(a)gmail.com> wrote: > > On Aug 23, 2007, at 9:14 AM, Jernej Azarija wrote: > > > Hello, > > > > I've encountered this issue too. Specifically, when a lot of calls > > to printf() have been made, the output looks messy. eg : > > > > printf("foo\n"); > > printf("bar\n"); > > > > Ends up written in system.log as : > > > > fobaro > > > > (just a banal example). > > > > Amazing. > > One of the most common problems faced when programming in the kernel > is use of "standard" functions—things like printf or bcopy. Many > commonly used standard C library functions are implemented in the > kernel. In order to use them, however, you need to include the > appropriate prototypes, which may be different from the user space > prototypes for those functions, and which generally have different > names when included from kernel code. > > In general, any non–I/O Kit header that you can safely include in the > kernel is located in xnu/bsd/sys or xnu/osfmk/mach, although there > are a few specialized headers in other places like libkern and libsa. > Normal headers (those in /usr/include) cannot be used in the kernel > (or rather, cannot be used 'properly'). > > If the standard C function you are trying to use is not in one of the > following files, chances are the function is not supported for use > within the kernel, and you need to implement your code in another way: > > <sys/systm.h> (printf can be used with this) > <sys/buf.h> (buffer cache functions like bread) > <sys/dirent.h> (directory entries) > <sys/errno.h> (Error numbers) > <sys.kernel.h> (kernel special variables) > <sys/lock.h> (spinlocks) > <sys/malloc.h> (malloc) > <sys/queue.h> (queues) > <sys/rand.h> (random generation numbers) > <sys/systm.h> (bzero, bcopy.. etc) > <sys/system.h> (timeout, untimeout) > <sys/time.h> (time functions) > <sys/types.h> <mach/mach_types.h> (standard type declarations) > <sys/ucred.h> (user credentials) > <sys/utsname.h> (os and system information) > > > > > > > I checked printf() implementation and it seems that loocking *is* > > handled correctly so I'm really wondering what's the problem behind > > it. > > > > -----Original Message----- > > From: darwin-kernel-bounces+jernej.azarija=hermes- > > softlab.com(a)lists.apple.com on behalf of Jeremy Pereira > > Sent: Thu 8/23/2007 9:35 AM > > To: JanakiRam > > Cc: darwin-kernel(a)lists.apple.com > > Subject: Re: printf logs are not getting printed properly on > > system.log > > > > On 23 Aug 2007, at 06:05, JanakiRam wrote: > > > > > Hi ALL, > > > > > > I'm newbie to this kernel prorgamming. Please clarify my > > > following query. > > > > > > I'm using printf for logging messages from my kext. One > > > observation is all my logs are not getting printed when i start my > > > kext using kextload. Its not consitent , how many logs are going > > > to get printed every time i load the kext. > > > > > > Please help me to solve this. Thanks in Advance. > > > > I've seen the same problem. I assumed it was because of overrunning > > some buffer somewhere i.e. producing too much output for the kernel > > logging system to cope with. > > > > > > > > > > > > > -JanakiRam. > > --- > Draichis > > draichis(a)gmail.com > draichis(a)craplandia.org > http://draichis.craplandia.org > > "I know that fewer people are won over by the written word than by > the spoken word and that every great movement on this earth owes its > growth to great speakers and not to great writers." > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/darwin-kernel/bogvardi%40gmail.com > > This email sent to bogvardi(a)gmail.com > _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: printf logs are not getting printed properly on system.log
by Draichis 23 Aug '07

23 Aug '07

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Dkim-signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=SZ3QUhrE23CWRILAKJiVZjjHaimh3HK2LkfK5dV2KTueEp6fesB+W6cLHO7yJww/EfI44HA9OkyWacG+p95irv1kPoEkAQEYHQDmxNxQbS1YFFF9kzui24hwzatqIx49Byy2RwvKTqtxcrZY28y/RPadgjv3iX6GGVADdCp9QMs= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:in-reply-to:references:mime-version:content-type:message-id:cc:content-transfer-encoding:from:subject:date:to:x-mailer; b=QRMLH1bp/bVVrthcXtZIw9D1XVRP98T++5FLJpJN2lfK9B9KqdVyKcNB7RTK0b3bPCjxV1OKumh/z9Em/+sceYkuLQW7ZVkLNyVGN50ZpdQzVyHzhDSh0a7iFNzhje/UEO8OGmisy3OZlWz2Fqmdh5+xiyOQQ5jmFFAaPEBze80= On Aug 23, 2007, at 9:14 AM, Jernej Azarija wrote: Hello, printf("foo\n"); printf("bar\n"); Ends up written in system.log as : fobaro (just a banal example). Amazing. <sys/systm.h> (printf can be used with this) <sys/buf.h> (buffer cache functions like bread) <sys/dirent.h> (directory entries) <sys/errno.h> (Error numbers) <sys.kernel.h> (kernel special variables) <sys/lock.h> (spinlocks) <sys/malloc.h> (malloc) <sys/queue.h> (queues) <sys/rand.h> (random generation numbers) <sys/systm.h> (bzero, bcopy.. etc) <sys/system.h> (timeout, untimeout) <sys/time.h> (time functions) <sys/types.h> <mach/mach_types.h> (standard type declarations) <sys/ucred.h> (user credentials) <sys/utsname.h> (os and system information) On 23 Aug 2007, at 06:05, JanakiRam wrote: > Hi ALL, > > I'm newbie to this kernel prorgamming. Please clarify my > following query. > > I'm using printf for logging messages from my kext. One > observation is all my logs are not getting printed when i start my > kext using kextload. Its not consitent , how many logs are going > to get printed every time i load the kext. > > Please help me to solve this. Thanks in Advance. I've seen the same problem. I assumed it was because of overrunning some buffer somewhere i.e. producing too much output for the kernel logging system to cope with. > > > -JanakiRam. --- Draichis draichis(a)gmail.com draichis(a)craplandia.org http://draichis.craplandia.org _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… I've encountered this issue too. Specifically, when a lot of calls to printf() have been made, the output looks messy. eg : One of the most common problems faced when programming in the kernel is use of “standard” functions—things like printf or bcopy. Many commonly used standard C library functions are implemented in the kernel. In order to use them, however, you need to include the appropriate prototypes, which may be different from the user space prototypes for those functions, and which generally have different names when included from kernel code. In general, any non–I/O Kit header that you can safely include in the kernel is located in xnu/bsd/sys or xnu/osfmk/mach, although there are a few specialized headers in other places like libkern and libsa. Normal headers (those in /usr/include) cannot be used in the kernel (or rather, cannot be used 'properly'). If the standard C function you are trying to use is not in one of the following files, chances are the function is not supported for use within the kernel, and you need to implement your code in another way: I checked printf() implementation and it seems that loocking *is* handled correctly so I'm really wondering what's the problem behind it. -----Original Message----- From: darwin-kernel-bounces+jernej.azarija=hermes- softlab.com(a)lists.apple.com on behalf of Jeremy Pereira Sent: Thu 8/23/2007 9:35 AM To: JanakiRam Cc: darwin-kernel(a)lists.apple.com Subject: Re: printf logs are not getting printed properly on system.log "I know that fewer people are won over by the written word than by the spoken word and that every great movement on this earth owes its growth to great speakers and not to great writers." This email sent to site_archiver(a)lists.apple.com

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Memory Restriction in Kext
by JanakiRam 23 Aug '07

23 Aug '07

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Re: printf logs are not getting printed properly on system.log
by JanakiRam 23 Aug '07

23 Aug '07

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Re: printf logs are not getting printed properly on system.log
by Rodney 23 Aug '07

23 Aug '07

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