December 2009 - Darwin-dev - lists.apple.com

comparative analysis of safari, chrome and firefox startup
by Joel Reymont 10 Dec '09

10 Dec '09

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=domainkey-signature:received:received:from:content-type :content-transfer-encoding:subject:date:message-id:to:mime-version :x-mailer; bh=4X0m8X3KfaDf3FA0cIJloqUpPtBIcA6H5cI7F94mxVE=; b=qI/tjrl4NXlW+qkyJzMJoFvCRR2fB5Q9I09CDHxDnPQzpOqYkREJyxP73RuUok2H0S 3FoaLgmWOoYUX+ck2Jja7tn+G8OwO2JOkn4/4S0u8bfneXRVPTui85+32mlsJzrwdagx zIN85/jrmOhOqIXiDZd/rQGwaziNh+B23IOrQ= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:content-type:content-transfer-encoding:subject:date:message-id :to:mime-version:x-mailer; b=nxBqvdLZSZwCvlJdhTaF3g3h+EKixtGzkVstvlVU+O/lcmcxN9zg9yb2ueTToWlJ7z p37UH85B/dkmxo5Wmyx6TzIJebMdml/05/R6jlNMrh4RcXLGkeAgmsbqCF4P34IP2bLP 4spmNW1FgzZJLPnFh8QHKrPysHcOSEmBBgc1s= Folks, Is my analysis of Safari, Google Chrome and Firefox startup on Snow Leopard correct [1]? Do you have any comments or anything to add? I'm puzzled by the Page Cache Hit time in Google Chrome. I wonder if it means good code locality? The link to the zip file with System Trace Shark profiles is in the URL field of the bug. Thanks in advance, Joel [1] https://bugzilla.mozilla.org/show_bug.cgi?id=533944 --- Mac hacker with a performance bent http://www.linkedin.com/in/joelreymont _______________________________________________ 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: zero-fill and memory allocation size
by Joel Reymont 10 Dec '09

10 Dec '09

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=domainkey-signature:received:received:subject:mime-version :content-type:from:in-reply-to:date:cc:content-transfer-encoding :message-id:references:to:x-mailer; bh=hvlkYfwcgeeM3Xv31yGOQ7iU/SfnIYQAPm6KRll7sHQ=; b=ZJE7DM/HgNr0BjYEv+rw7cIXp9xdMz2bsmv+osTwxpbvYPldKPZKN7Zz2N74/gzlV1 2f4wWf+d3dlGqnnNOKvG/7lzjtxVQGmyx0kQ+zX3phBThBbiEmsJJii9IDUhcgC7R+8n t0p/qMFkCjk8RKH1RlSMB0F5PSsc8nXFZ6VyE= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; b=mrgl977PbaffRC9uVrpuIY/Wppt6CdqnRcDWppYGfKzFIl6xGiAjjtYVsw7f9Wx9kn BPyvU2qeZ4BxGKKfS1sMhtwGBjS06BXlZc3XUpIaw8jx1J9SERon1lunPKN2Fn7Bdwvl jIgCaUEphWBPZgPmK5NMnj7sqVIeRQT6FqcCQ= Terry, Thank you for your extensive comments. I assume you meant to send them to the list. I was referring to a previous discussion and the 15K mentioned in it. Does that still stand? Thanks, Joel [1] http://lists.apple.com/archives/PerfOptimization-dev/2008/Nov/msg00033.html On Dec 10, 2009, at 8:51 PM, Terry Lambert wrote: > On Dec 10, 2009, at 11:43 AM, Joel Reymont wrote: >> I understand that allocations over a certain size come from the virtual memory manager and have to be zero-filled. Is 15K still that size? > > > Assuming this is an allocation by a process: > > All processes run in virtual address spaces, so all memory in them comes from the VM system. > > Virtual pages in processes are not backed by physical pages until they are used. When this happens, the physical page that gets assigned to the virtual address in the process is zero-filled. Failure to do this could leak sensistive information from the process previously using the physical backing page into the new process. So this is not optional. > > Once a physical page is allocated to a virtual page in a process, it can be used by the process. If the process fills it with data, that page contains the data that was put in it. > > If a process implementation an allocation/release mechanism, such as malloc/free, or uses a system library that does so, when a page is freed it is not necessarily immediately returned to the system. For some implementations, it is not *ever* returned to the system. > > If a process using an allocation/release mechanism allocates memory, dirties it, and releases it, and then makes a subsequent allocation, that allocation may contain the previous data which dirtied the page. This is typical, since zeroing the memory is more expensive than doing nothing, and process itself does not partition security zones, since it only supports a single virtual address space, and so can not protect against accesses by other threads within itself. > > Thus you MUST NOT _depend_ on the contents of the memory you allocate being zeroed. > > If you need zero-filled memory, you will need to bzero it yourself. > > For some memory allocators, you can bzero the memory before freeing; however, other implementations will write their bookkeeping information into the freed memory (for example, free-list pointers in the memory itself to avoid out of band free list memory overhead), so you can not depend on post-use-zeroing-before-freeing memory to cause your allocator to always give you zeroed memory. > > If you need zeroed memory always, you will likely need to write your own allocator. > > Security note: > > If you use memory (allocated or otherwise) in a privileged situation to contain security sensitive information, such as passwords, then you will need to zero the memory after use before dropping privilege, or an attack on your program in an unprivileged state may get access to the data it had access to before it dropped privilege. > > -- Terry --- Mac hacker with a performance bent http://www.linkedin.com/in/joelreymont _______________________________________________ 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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zero-fill and memory allocation size
by Joel Reymont 10 Dec '09

10 Dec '09

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=domainkey-signature:received:received:from:content-type :content-transfer-encoding:subject:date:message-id:to:mime-version :x-mailer; bh=ukUVx5PDqXdZu/K2yAetw+vSIA1JBvoOGb102G/465c=; b=H4rsi8cNm5ZsOeZptjBOlu/Kd4zw1Tbwsf/fq5TpvncjVQLR3WWYvyvs/4o9O+hk6e ST1dqlrVOVirxEwTGPMhVRI/OsFO2YUya1CSaP4rorBGZIVN+5Hm5l2nkKexWSX2JpIQ zolTDVgQ20mHMz/V2HkjenFelPmW6ZinYBZ6U= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:content-type:content-transfer-encoding:subject:date:message-id :to:mime-version:x-mailer; b=qmuKNFwUGNyN3Ao/4OJPATnvBsiAss9Bd0gzjcTC+dYaHdH6Cgq3JiF164ZnrQLw6y Okgv6P03PH+mtwIZJmkCfsk0KOCZ3ou6iXiFl0kJZeXlqv1E6sPFLi5pZsr5r1kU6fCa U4ZBn/QeVTobPy8RJUYYcup9G06JdwilwUWZs= I understand that allocations over a certain size come from the virtual memory manager and have to be zero-filled. Is 15K still that size? Thanks, Joel --- Mac hacker with a performance bent http://www.linkedin.com/in/joelreymont _______________________________________________ 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: Socket Filter NKE
by Vincent Lubet 09 Dec '09

09 Dec '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Jakub, Another idea would be to use an IP filter to intercept the incoming FIN packet and re-inject when you know the pending data have been processed. Have a look at <netinet/kpi_ipfilter.h> for more information about IP filters.It's a lower level API than socket filter so you will have to match the addresses and ports with the corresponding socket. Vincent On Dec 9, 2009, at 7:09 AM, Jakub Bednar wrote: > Hi Josh, > > thanks a lot for a fast response. I have run some tests with redirecting outgoing connections both on Leopard and Snow Leopard and it works just fine. I just wonder, can the NKE redirect also incoming connections? > > Jakub > > On Dec 3, 2009, at 7:20 PM, Josh Graessley wrote: > >> >> The recommeded solution is to manipulate connections to connect to >> your process instead of their intended destination. You may pass the >> intended destination out of band to your processs and then relay the >> data in user space between the socket connection from their process >> and your socket connection to their intended destination. >> >> Sent from my iPhone >> >> On Dec 3, 2009, at 7:38, Jakub Bednar <jakub.bednar(a)avg.com> wrote: >> >>> Hello list, >>> >>> I am writing a socket filter NKE that will intercept any TCP >>> connections, pass its data to user-space processing using >>> SYS_PROTO_CONTROL and then re-inject them back. I have read many >>> posts in Apple mailing lists and the guides discussing NKE and >>> Kernel Programming and up to now everything worked great. >>> >>> Today I have found a problem with one-way traffic ended with FIN >>> sequence. In this case, the TCP reacts on the FIN and a >>> sf_detach_func is called to my filter, while I still have some data >>> swallowed and waiting for user-space to process it. >>> >>> I can't reinject the packets as I don't want to leave any data >>> unprocessed. >>> If I drop the packets, the client won't get them all, leading to >>> errors. >>> >>> Can anyone please point me to any documentation discussing the >>> socket filters in more detail? Can I msleep in sf_notify_func or >>> sf_detach_func to let user-space process finish the scanning? Or can >>> I somehow deny the socket detach and do it myself later? _______________________________________________ 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: Socket Filter NKE
by Josh Graessley 09 Dec '09

09 Dec '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi Jakub, There's no reason it wouldn't work for incoming connections but it will be a little tricky. You'll want to create the listening socket that incoming connections will initially connect to. When an application wants to accept incoming connections on a TCP socket, it must first call listen. I think your filter will have an opportunity to intercept the listen call (it's been a really long time since I was looking at that code). At the point of the listen, you'll need to figure out what address the socket is bound to (sock_getsockname). You could probably bind the socket to a new address and then tell your process to open a listening socket bound to the original address/port pair. If the port is zero, the socket your filtering did not specify a port, so your application can also bind do zero. After you've done this, you'll need to over ride the getsockname function for that socket to return whatever address/port your filtering applications listening socket is bound to. This should result in your application having a listening socket bound to the address/port that the application you're intercepting thinks it is listening on. When a connection comes in, your process should open a second socket to the listening socket your process is intercepting (at the new address/port that you rebound to). I'm not certain you can call bind a second time on a TCP socket, although if the socket hasn't been connected yet or listening hasn't started, I think that should work. If changing the bind isn't an option, you'll have to do some ugly stuff around intercepting the initial bind. That's going to be especially gross because at the point the bind occurs, you won't know if the application wants to use that socket for an inbound or outbound connection. Hope this helps at least give you some ideas. Sorry to be so vague. -josh On Dec 9, 2009, at 7:09 AM, Jakub Bednar wrote: > Hi Josh, > > thanks a lot for a fast response. I have run some tests with redirecting outgoing connections both on Leopard and Snow Leopard and it works just fine. I just wonder, can the NKE redirect also incoming connections? > > Jakub > > On Dec 3, 2009, at 7:20 PM, Josh Graessley wrote: > >> >> The recommeded solution is to manipulate connections to connect to >> your process instead of their intended destination. You may pass the >> intended destination out of band to your processs and then relay the >> data in user space between the socket connection from their process >> and your socket connection to their intended destination. >> >> Sent from my iPhone >> >> On Dec 3, 2009, at 7:38, Jakub Bednar <jakub.bednar(a)avg.com> wrote: >> >>> Hello list, >>> >>> I am writing a socket filter NKE that will intercept any TCP >>> connections, pass its data to user-space processing using >>> SYS_PROTO_CONTROL and then re-inject them back. I have read many >>> posts in Apple mailing lists and the guides discussing NKE and >>> Kernel Programming and up to now everything worked great. >>> >>> Today I have found a problem with one-way traffic ended with FIN >>> sequence. In this case, the TCP reacts on the FIN and a >>> sf_detach_func is called to my filter, while I still have some data >>> swallowed and waiting for user-space to process it. >>> >>> I can't reinject the packets as I don't want to leave any data >>> unprocessed. >>> If I drop the packets, the client won't get them all, leading to >>> errors. >>> >>> Can anyone please point me to any documentation discussing the >>> socket filters in more detail? Can I msleep in sf_notify_func or >>> sf_detach_func to let user-space process finish the scanning? Or can >>> I somehow deny the socket detach and do it myself later? >>> >>> Thanks a lot for Your help, >>> >>> Jakub >>> _______________________________________________ >>> 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/jgraessley%40apple.com >>> >>> This email sent to jgraessley(a)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: Font Rendering Kexts
by Alastair Houghton 09 Dec '09

09 Dec '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha1; c=relaxed; d=alastairs-place.net; h= subject:mime-version:content-type:from:in-reply-to:date:cc: content-transfer-encoding:message-id:references:to; q=dns/txt; s= aug07; bh=LWsqPu9socpVPyTw/puz/gFuy18=; b=ddv9XSzJ02+8edYziK1gD7 1RUrDdGJKCvSO0biqxJz8QuG+AaG2FjfEDJW4MpHh5ab+8/KB/1aTfZpUL52uu9u Gg5nmnQhEU2I9irmCUhpGINucZia57QhDzdnLTa+ZBnLpIoBAjCkE1lHRp6YjSI5 8766aPPBncgcR79K+JkFA= On 9 Dec 2009, at 16:11, Abius X wrote: > I've had a problem on Snow Leopard which seems to occur on every MacBook I upgrade to SL. > The installation process fails at some kexts and the font rendering for Persian language is bogus, There are | lines instead of non-breaking spaces in words! > > I assumed Snow Leopard added the functionality to render Windows True Type fonts out of the box, > > Please guide me in the correct path to figure this out more specifically. Font rendering isn't kernel functionality and as such has little to do with kexts or with the underlying Darwin system. Mac OS X has always (at least in every version I've used) been able to render "Windows TrueType" fonts as well as AAT fonts, OpenType fonts and PostScript fonts. If you're having font rendering problems the place to post is probably quartz-dev. Kind regards, Alastair. -- http://alastairs-place.net _______________________________________________ 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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Font Rendering Kexts
by Abius X 09 Dec '09

09 Dec '09

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=domainkey-signature:received:received:from:content-type :content-transfer-encoding:subject:date:message-id:to:mime-version :x-mailer; bh=8InHyPzaTEg7o+OTQAjpiekpqol/Ehn2sohg8jnKwL0=; b=Laqu+uwbGhYnGFuuUeBbuSRp1dzgtp+YMU9dlOSp2zhaJZfUcAK9p9oMvhbGKP/XSz M7746RedWWiNmFsNArjQm3RqZC1EAk4/lI4JIKKcQq5cbXtTVknkPd+/1rtj4qf06RWk 7q8EJZOniTn+i1wQZNsfTLx3GeJgutRqQYyOk= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:content-type:content-transfer-encoding:subject:date:message-id :to:mime-version:x-mailer; b=GEAHnioXHClOJs9iBk8b0g90+wlURU2gkwwVksfJB9j0LoAzYSFixBqB2CheX/iB6w S4VS2mV6EM4OoMaIk49RUQs9c1px71ifKAcT1SXhY9VC3ZmAre0qZ1V9XO4oe2fPZX+/ B6RrefRKoKZ39RGra3Q4exL/Tt12hnB5dadw4= Hi people, I've had a problem on Snow Leopard which seems to occur on every MacBook I upgrade to SL. The installation process fails at some kexts and the font rendering for Persian language is bogus, There are | lines instead of non-breaking spaces in words! I assumed Snow Leopard added the functionality to render Windows True Type fonts out of the box, Please guide me in the correct path to figure this out more specifically. Regards AbiusX _______________________________________________ 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: Socket Filter NKE
by Jakub Bednar 09 Dec '09

09 Dec '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi Josh, Jakub On Dec 3, 2009, at 7:20 PM, Josh Graessley wrote: The recommeded solution is to manipulate connections to connect to your process instead of their intended destination. You may pass the intended destination out of band to your processs and then relay the data in user space between the socket connection from their process and your socket connection to their intended destination. Sent from my iPhone On Dec 3, 2009, at 7:38, Jakub Bednar <jakub.bednar(a)avg.com> wrote: Hello list, I am writing a socket filter NKE that will intercept any TCP connections, pass its data to user-space processing using SYS_PROTO_CONTROL and then re-inject them back. I have read many posts in Apple mailing lists and the guides discussing NKE and Kernel Programming and up to now everything worked great. Today I have found a problem with one-way traffic ended with FIN sequence. In this case, the TCP reacts on the FIN and a sf_detach_func is called to my filter, while I still have some data swallowed and waiting for user-space to process it. I can't reinject the packets as I don't want to leave any data unprocessed. If I drop the packets, the client won't get them all, leading to errors. Can anyone please point me to any documentation discussing the socket filters in more detail? Can I msleep in sf_notify_func or sf_detach_func to let user-space process finish the scanning? Or can I somehow deny the socket detach and do it myself later? Thanks a lot for Your help, Jakub _______________________________________________ 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/jgraessley%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… thanks a lot for a fast response. I have run some tests with redirecting outgoing connections both on Leopard and Snow Leopard and it works just fine. I just wonder, can the NKE redirect also incoming connections? This email sent to jgraessley(a)apple.com This email sent to site_archiver(a)lists.apple.com

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Re: shmget() returning EINVAL for constant size and flags
by rohan a 07 Dec '09

07 Dec '09

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=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=M3NtF5lhObIZmYDhQCpDc78ddV6ch1lfY63PXlRN0V0=; b=YuG+keroAQWUZ3C17sf0hfmwLMBNoBZHU3kfuk7sy2BguC/jPOtHM2TmwSPp2mBDAI 8O46FKecVOlH2nH6kPRJzM5Vy4Xhf+1nxRkGv32h0xl7Dg1gxxuOqmeXYpoyVsiS9RNL Isjklt+KlQYdQY03UOw+BWjP5DBkX0QR1hWL8= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=rHRCQOWFLHDmP0jihSE1wqFcAuuYyqt9TBqVMJ4kKWXGAJTG1uJdG64t72NRXGFNad lAVDgvqLJ0pDJ0Hvac7VmpGgOZ9hvcerQ1ryh8B6mJP+Q/fsFrSzKPFEqdNNKgJlmINm xYkF7rmchiGMSfDkU9LmLjFkWm/vsN/cQq7mU= shmget() should be returning EINVAL only if no memory segment is to be created (IPC_CREAT not specified) and EEXIST if memory segment is to be created. However, Mac OS X is returning EINVAL even when I am using shmget() to create a memory segment. The same program on Linux/Hp-UX works fine (returns EINVAL when I call shmget() without IPC_EXCL and EEXIST when I call it with IPC_EXCL) Also the Mac OS X man page is saying that EINVAL would be returned when no shared memory segment is to be created and a segment exists with a size lesser then size requested. Has anyone faced this problem. Any solutions / comments on this ? Thanks, Rohan On Sat, Dec 5, 2009 at 8:00 PM, rohan a <info1686(a)gmail.com> wrote: > Hi, > > I do not think the key is invalid because shmget() with the same key > has succeeded several times. > Is it possible to use another key if either EEXIST or EINVAL is > returned or should I necessarily have to check using shmctl() if > another process is using that key ? > > Thanks, > Rohan > > On Sat, Dec 5, 2009 at 11:53 AM, Tyler Sample <tyler.sample(a)gmail.com> wrote: >> EINVAL is also returned if your key is entirely invalid. Double check that >> before your function call. >> >> If that's not the problem, if the shmget call fails, you can try making >> another call with the size set to 0, then make sure that call succeeds. Then >> you can use shmctl to find out about the memory....In particular, you can >> print the size. If it's something reasonable, you probably have a duplicate >> key with another process. >> >> >> >> >> >> ----- Original Message ----- From: "rohan a" <info1686(a)gmail.com> >> To: <darwin-dev(a)lists.apple.com> >> Sent: Friday, December 04, 2009 9:30 PM >> Subject: shmget() returning EINVAL for constant size and flags >> >> >>> Hello All, >>> I am using shmget() to allocate shared memory in my backup/restore >>> utility. >>> >>> int shmget(key_t key, size_t size, int shmflg); >>> >>> The size and shmflg I am passing are always constant. If shmget() >>> returns EEXIST I try again with another key until shared memory is >>> allocated. >>> >>> On some occasions, shmget() fails and I am getting an EINVAL error. >>> I dont think the arguments are invalid because, I am using constant >>> values for size and shmflg for every call and most of the calls are >>> successful. >>> >>> The Man page says this for EINVAL : >>> >>> [EINVAL] No shared memory segment is to be created, and a >>> shared memory segment exists for >>> key, but the size of the segment associated >>> with it is less than size, which is non-zero. nonzero. >>> zero. >>> >>> However, with every shmget() call, I use the same size 524288 and same >>> flags with different key ofcourse. >>> >>> Then why should I get an EINVAL ? >>> >>> Is it possible that another application is allocating shared memory >>> using this key but a size lesser than 524288 ? >>> >>> Along with checking EEXIST for existence of a memory location with >>> this key should I also check for EINVAL ? >>> That is if EINVAL is returned, should I try to allocate with another key ? >>> >>> Thanks, >>> Rohan >>> _______________________________________________ >>> 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/tyler.sample%40gmail.com >>> >>> This email sent to tyler.sample(a)gmail.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: which pages of the file are in the cache
by Juan Manuel Palacios 05 Dec '09

05 Dec '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Dec 4, 2009, at 5:31 AM, Jonas Maebe wrote: > > On 04 Dec 2009, at 03:53, Greg Parker wrote: > >> On Dec 3, 2009, at 6:19 PM, Juan Manuel Palacios wrote: >>> Thing is, it *used* to be called MacOS, without any spaces, back in 'them pre-NeXT days, i.e. MacOS 9 and prior, all the way down to MacOS 7.6. Even prior to that it used to be called something completely different, namely "System Software", all the way down to its first 1.0 iteration, if I'm not mistaken. Once Stevie came back on board and we were dealing with the NeXT based Mac OS that we all now know and love, Apple did a complete Nineteen Eighty-Four on us and renamed the entire thing "Mac OS", with the space, rewriting every name and reference everywhere all the way back to 7.6 days, to make us believe nothing else had ever happened, very Ministry of Truth of you, thank you very much! ;) >> >> The "Mac OS" name, as introduced with Mac OS 7.6, had a space in it. This was well before the NeXT deal. >> http://www.altfuels.org/lilolmcs/graphics/atmnm8_1.gif >> http://www.apple-collection.com/PhoSysteme/S1.jpg >> http://www.apple-collection.com/PhoSysteme/Sys.Mc.7.6.B.jpg > > That's really odd, I was also 100% convinced that it was called "MacOS" rather than "Mac OS" between 7.6 and 9.2.2... I wonder why. Yeah, me too! Maybe O'Brien did his work on us instead and we just... hhhmm, "forgot" ;) In any case, the "System Software" name, most of the times simply bundling a System x.y release and a Finder x.y release, is indeed confirmed by this picture http://en.wikipedia.org/wiki/File:Macintosh_System_7.5.3_screenshot.png , so at least I wasn't entirely wrong! - jmpp _______________________________________________ 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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