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From: greg.freemyer@gmail.com (Greg Freemyer)
To: kernelnewbies@lists.kernelnewbies.org
Subject: link question
Date: Wed, 29 Jun 2011 17:10:53 -0400	[thread overview]
Message-ID: <BANLkTimhxBJkiRDMjUO2+LAQE_9uKuyODA@mail.gmail.com> (raw)
In-Reply-To: <4E0B629E.6030302@tysdomain.com>

On Wed, Jun 29, 2011 at 1:36 PM, Littlefield, Tyler <tyler@tysdomain.com> wrote:
> I have a quick question; this is something I haven't been able to figure
> out. By using the kernel headers you can call functions that are defined
> in the kernel, but you don't actually have to link to the kernel or any
> sort of library. How does this work? How does compiled code call the
> function if it doesn't link to it in some way or another?.

Is this a question about userspace apps or kernel modules?

Userspace apps link to glibc which in turn has assembly instructions
embedded to call into the kernel.

Kernel Modules get a different kind of magic, but I'm not sure of those details.

Greg

      parent reply	other threads:[~2011-06-29 21:10 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-29 17:36 link question Littlefield, Tyler
2011-06-29 17:46 ` Mulyadi Santosa
2011-06-29 17:56   ` Littlefield, Tyler
2011-06-29 18:40 ` Greg KH
2011-06-29 20:05   ` Guillaume Knispel
2011-06-29 21:10 ` Greg Freemyer [this message]

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