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

Re: where is fstat
by Kevin Van Vechten 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jan 16, 2009, at 1:02 PM, Joel Reymont wrote: Better yet, use DTrace: #!/usr/sbin/dtrace -s syscall::fstat:return /execname == "myprocess" && arg0 != 0/ { printf("%s[%d] fstat returned %d\n", execname, pid, arg0); ustack(); } _______________________________________________ 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… It's a syscall, so it's only a stub in libc. It's actually defined in the kernel (the xnu module). Also, assuming that I can sudo, is it possible to set a breakpoint in kernel space to see where my fstat call is failing? This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Joel Reymont 16 Jan '09

16 Jan '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:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=KLeor0MScXraZ/wzvTkaKKb63RrOwy6OegfKIBAqjTg=; b=YdtMJ5Kq3Pn5g7Gxn8rnJnPsF0leUGk9vVyoUWlWLUWT14RjPYfFsR5wcd4l0owUlC WVXBust8JhomrI/uQDv7ZmBhS3yozQesxvG6+k1RlhbIEfzY94fE4JSVznxbco9gcGez OAeb5Lgzkw8bdCOXWrj4ozBZ/ZfE8Iusf/z44= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=P1yrd2FaftTtKNS7v/o1yv1H5OG4KWXLpetOOR0TlHUMt8IUE7RLmD8g56CZN0geZN z6jdbQdRtqPkW91BPmimS9TJ+Pq/sUds6e5leC2hVcMv7VzS0R+wC/gKWagFejXxM99G Zq3v2zpM1/qXiFLUgdzQjkfZ8RpEezjPLGMRU= Thanks, Joel --- http://twitter.com/wagerlabs _______________________________________________ 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… It's a syscall, so it's only a stub in libc. It's actually defined in the kernel (the xnu module). Also, assuming that I can sudo, is it possible to set a breakpoint in kernel space to see where my fstat call is failing? This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Joel Reymont 16 Jan '09

16 Jan '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:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=uSp7P/Gy5X4kt6yBBqbi1vloQHaDYnJG8pPnjwVWxFo=; b=gjhyP1+/YtqlQ9ZNsa+5oNgOTb7cPDMj7eOFppyrpsdwEzh6Q/ouf39tkHLYwAcBKp kHIUmH3c8Aa+ozi+ALgTShWKVVf29YsE3G57tWTZdlKbJQ4tDmLw0RYniSGEdpwzenSr MhJEjYjafsg5Gu/QvRc600BMSCPdF6ji40EbE= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=mWqpkCUsdPvRLSBB2WLbvDYloQNpkMVVomG4VmDB3p05aVDYWxJeaDHR5em9EDNj17 HYeCGKEyDCvbLRH5+jqlB03EpbGqJxAoMxAYLuRVBpc7+U/2ZC9mMBzhUC2lZ+ZOmhkx AkC0kV8dm6d10iAZfbNwiYIhrKQffsF+t9bDU= On Jan 16, 2009, at 8:25 PM, Jason Coco wrote: I'll go dig through the kernel sources in the meantime. Thanks, Joel --- http://twitter.com/wagerlabs _______________________________________________ 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… It's a syscall, so it's only a stub in libc. It's actually defined in the kernel (the xnu module). A follow-up question then... under what conditions can fstat return EINVAL (invalid argument)? I can call fstat for stdin, stdout and stderr just fine but as soon as I give it my fd (opened read-only), it gives me an error. This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Jason Coco 16 Jan '09

16 Jan '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:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=XLVN6YmiDgqeZB58mT7aXAd9E/VfBsKg2qyfdzOk/uo=; b=M76buO0zyX8Oo3RnE5zfHFl1wwdPkWrmLQQXZixOGoyOF+9AHlHwPpsOLYcrS2HucN fZKEjy5S3ioYKU+sIVc58xpXyn+uX7p5si+aWIRT7sbvakKXQjMyexvmRYhgj3lRnAls W67TLc3W2JvRju5OV6Mgco8dsv/YkUPn9mPOQ= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=RZzNm7h0b5Tf2vGsB+OoWDrVRPKWYFdQh2KWI7kUtepbOPBeiisYvNAukA2GKdqceM CRdyPTNYuD6pvTybLaRXLVCv032WXZfSJ8VOOvr4QHqdqNcvDEUJ6ejn2mOmAT7nWMee 1dwrLhVMG6PGPR+LbrtG/3/3cQ54K+dr7kMMo= On Jan 16, 2009, at 15:21 , Joel Reymont wrote: A silly question but... What source file in libc has the definition of fstat? It's a syscall, so it's only a stub in libc. It's actually defined in the kernel (the xnu module). _______________________________________________ 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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where is fstat
by Joel Reymont 16 Jan '09

16 Jan '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:message-id:from:to :content-type:content-transfer-encoding:mime-version:subject:date :x-mailer; bh=rKGjGqLpUL3vcNi8q0jIjxa/ppdB6Bl+FB81aDwpeZI=; b=nywAHwk2IRdXIeecgWaofWTGc1jyN35n/usdPHA+Bsax4qhHWQ98lZrA0j6Xn/Cntr 3B732Y8rguAYltKulJI+yRP7Mdh1DA4SkseiTsqN934hkuwQRABTP5mZ8g7xL3lQqvW3 O1ryN0Fr2P5ZyvqIumQXudCwnt0Or5tBgxA8M= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:content-type:content-transfer-encoding :mime-version:subject:date:x-mailer; b=ur0knCaiEl8EoNNhgYDdLBHuap3HWIRY2IeP0pD15CEXWNbEVz2hKHIV9HXyNcqPJH CuNmmlFvGdQHbsV92RUl26sVmvG6wsYhNmLG5so/OUQvnVdfYHdfKDLSCXzlni/AF/B0 EUCU/HPs8XfewHFhuF+KfU/8Nk18mocv+c0NU= A silly question but... What source file in libc has the definition of fstat? Thanks, Joel --- http://twitter.com/wagerlabs _______________________________________________ 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: Descriptor Passing Mac OS X 10.5.4 ( X86_64 )
by Rohitash Panda 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Organization: Oracle Corporation User-agent: Thunderbird 2.0.0.19 (Windows/20081209) _______________________________________________ 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: bootstrap_register replacement
by Ed Wynne 15 Jan '09

15 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Task special ports are inherited across fork(2). -Ed _______________________________________________ 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 Jan 15, 2009, at 2:40 PM, Damien Sorresso wrote: 0. In parent, create a new port (Port A) to which you hold a receive right. 1. Insert a send right into that port. 2. Cache your current task bootstrap port. 3. Set the task bootstrap port to Port A. 4. fork(2) / exec(2) your child. 5. In the parent, set your task bootstrap port back to the cached port. 6. Have the child send a message to the parent (via its bootstrap port) requesting all the information it needs, perhaps including the parent's bootstrap port. 7. Optionally, have the child reset its bootstrap port to the parent's bootstrap port. #7 should not be optional. Frameworks and other system services may depend on the bootstrap port being what it claims. It should mandatorily be set back, ASAP. smime.p7s

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Re: bootstrap_register replacement
by Jean-Daniel Dupas 15 Jan '09

15 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Le 15 janv. 09 à 20:40, Damien Sorresso a écrit : Hello, Task special ports are inherited across fork(2). Thank you. This is exactly what I need. _______________________________________________ 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 15, 2009, at 4:13 AM, Jean-Daniel Dupas wrote: I just have a question. On 10.5, the bootstrap_register() doc said this method should not longer be used and give some alternatives like this one: 2) If the code was registering a dynamically generated string and passing the string to other applications, please rewrite the code to send a Mach send-right directly. My question is simple. To send the Mach send right, I need a send right to the target process. But to get a send right from the target process, it need a send right on the first process. That's why the bootstrap server exists. Maybe I miss something, but I do not understand how I can upgrade an app that was using the scenarios describe in 2). Is there some magic way to give a send right to another process ? AFAK, even passing an arbitrary port to a child process is not possible. 0. In parent, create a new port (Port A) to which you hold a receive right. 1. Insert a send right into that port. 2. Cache your current task bootstrap port. 3. Set the task bootstrap port to Port A. 4. fork(2) / exec(2) your child. 5. In the parent, set your task bootstrap port back to the cached port. 6. Have the child send a message to the parent (via its bootstrap port) requesting all the information it needs, perhaps including the parent's bootstrap port. 7. Optionally, have the child reset its bootstrap port to the parent's bootstrap port. Hope this helps. Sometimes I think we need a "general purpose special port" for things like this, but there's nothing particularly evil about using the bootstrap port for this purpose. This email sent to site_archiver(a)lists.apple.com

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Re: bootstrap_register replacement
by Damien Sorresso 15 Jan '09

15 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hello, Task special ports are inherited across fork(2). _______________________________________________ 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 Jan 15, 2009, at 4:13 AM, Jean-Daniel Dupas wrote: I just have a question. On 10.5, the bootstrap_register() doc said this method should not longer be used and give some alternatives like this one: 2) If the code was registering a dynamically generated string and passing the string to other applications, please rewrite the code to send a Mach send-right directly. My question is simple. To send the Mach send right, I need a send right to the target process. But to get a send right from the target process, it need a send right on the first process. That's why the bootstrap server exists. Maybe I miss something, but I do not understand how I can upgrade an app that was using the scenarios describe in 2). Is there some magic way to give a send right to another process ? AFAK, even passing an arbitrary port to a child process is not possible. 0. In parent, create a new port (Port A) to which you hold a receive right. 1. Insert a send right into that port. 2. Cache your current task bootstrap port. 3. Set the task bootstrap port to Port A. 4. fork(2) / exec(2) your child. 5. In the parent, set your task bootstrap port back to the cached port. 6. Have the child send a message to the parent (via its bootstrap port) requesting all the information it needs, perhaps including the parent's bootstrap port. 7. Optionally, have the child reset its bootstrap port to the parent's bootstrap port. Hope this helps. Sometimes I think we need a "general purpose special port" for things like this, but there's nothing particularly evil about using the bootstrap port for this purpose. -- Damien Sorresso BSD Engineering Apple Inc. smime.p7s

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bootstrap_register replacement
by Jean-Daniel Dupas 15 Jan '09

15 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hello, _______________________________________________ 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 just have a question. On 10.5, the bootstrap_register() doc said this method should not longer be used and give some alternatives like this one: 2) If the code was registering a dynamically generated string and passing the string to other applications, please rewrite the code to send a Mach send-right directly. My question is simple. To send the Mach send right, I need a send right to the target process. But to get a send right from the target process, it need a send right on the first process. That's why the bootstrap server exists. Maybe I miss something, but I do not understand how I can upgrade an app that was using the scenarios describe in 2). Is there some magic way to give a send right to another process ? AFAK, even passing an arbitrary port to a child process is not possible. This email sent to site_archiver(a)lists.apple.com

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