Usage of kern_* functions in kernel

John Baldwin jhb at freebsd.org
Fri Apr 27 19:03:09 UTC 2007


On Friday 27 April 2007 02:43:16 am Marc Lörner wrote:
> On Thursday 26 April 2007 19:49, John Baldwin wrote:
> > On Thursday 26 April 2007 08:08:19 am Marc Lörner wrote:
> > > Hello,
> > > I googled but found nothing about the usage of the kern_* functions
> > > (kern_open, kern_close, kern_pwritev, kern_preadv) that are located in
> > > vfs_syscalls.c
> > >
> > > When I use kern_open to open a file within the kernel, I get an error.
> > > When I use the normal vn_open function instead, all works well.
> > >
> > > So my question is which functions are recommended by you kernel-hackers
> > > for use within kernelspace?
> > >
> > > And here a second question: Is it possible to open/use the console 
driver
> > > in kernelspace within the functions mentioned above?
> > > If not, can you give me some pointers on where I can find this
> > > information!
> >
> > kern_XXX are generally used by system calls such as alternative ABIs, etc.
> 
> so, you would recommend using the vn_* functions instead?

In general userland should open files rather than the kernel.

-- 
John Baldwin


More information about the freebsd-hackers mailing list