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Date:      Mon, 23 Jul 2001 17:46:00 -0700
From:      Mike Smith <msmith@freebsd.org>
To:        rootx11@xfreek.mindriot.net
Cc:        freebsd-hackers@freebsd.org
Message-ID:  <200107240046.f6O0k0204188@mass.dis.org>
In-Reply-To: Your message of "23 Jul 2001 19:47:46 -0000." <20010723194746.418.qmail@xfreek.mindriot.net> 

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> Hello
> I am experimenting with kernel modules and am trying to write to a file.
> This is the syscall function (sorry of my terminology is messed up)
> 
> static int write_file(struct proc *p, void *arg) {
> 	struct write_args *wstructure;
> 	struct open_args *ostructure;
> 
> 	ostructure->path="/tmp/blehfile";
> 	ostructure->flags = O_CREAT;
> 	ostructure->mode = 0;
> 	wstructure->fd = open(p, ostructure);
> 	wstructure->buf = "Testing\n";
> 	wstructure->nbytes = 8; 
> 	return write(p, wstructure);
> }
> 
> Im not sure why, but that code crashes.  Was created with:
> echo Hi > /tmp/blehfile.  Also, is there an official freebsd kernel hackers
> guide?  Kernel programming is very interesting. ;-)

Write expects the data to be in userspace; you can't call it from the 
kernel.  (This is a bug.)

-- 
... every activity meets with opposition, everyone who acts has his
rivals and unfortunately opponents also.  But not because people want
to be opponents, rather because the tasks and relationships force
people to take different points of view.  [Dr. Fritz Todt]
           V I C T O R Y   N O T   V E N G E A N C E



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