On Thu, Jun 28, 2001 at 07:48:21PM +0100, Doug Rabson wrote:
> On Thu, 28 Jun 2001, Nicolas Souchu wrote:
> 
> > Hi folks,
> >
> > I have a char driver that must be opened by more than one process. The minor
> > index is not sufficient for this. Is there any process private data (void *)
> > in the devfs structure (or the opposite) I could point to with the minor index
> > of my device?
> 
> The only way I know of to do this is to get a new struct file with
> falloc() and install your own fileops. You can then set p->p_dupfd to the
> new file descriptor and return ENXIO. The caller will magically use the
> new struct file. For an example, see streamsopen() in
> sys/dev/streams/streams.c.

Ok, it seems to do part of the job. But this won't change the content of the
file struct. Does anything ensure that the f_data of the freshly allocated
struct file won't be used by vfs? Is the new struct file only local to my
device driver?

Otherwise, I could write my own falloc() which would allocate a struct file
compatible with the original one like this:

struct my_file {
        struct file original;
        void *my_private;
        ...
};

Nicholas

-- 
Alcôve Technical Manager - [EMAIL PROTECTED] - http://www.alcove.com
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