(Fwd) Re: SCSI tape data loss

[Dan Langille]

On 31 Aug 2003 at 20:35, Dan Langille wrote:

> On 28 Aug 2003 at 13:11, Dan Nelson wrote:
> 
> > Daniel Eischen wrote:
> > > Can I ask a question?  When writing to a character/block special file
> > > in non-blocking mode, are there any instances where 0 can be returned
> > > from the write() other than when writing to a tape device?
> > > 
> > > The only way I can see to fix this in libc_r is to fstat() the
> > > descriptor when the threads library initializes it (uthread_fd.c)
> > > and save st_mode for that fd.  Then in write() check to see if
> > > it is S_ISCHR() or S_ISBLK() and 0 was returned.  It could
> > > break out of write() if that was the case and return 0 to
> > > the caller.  But this doesn't work if you can get 0 back
> > > from a write to other devices.
> > 
> > I would be inclined to always pass a zero return from read or write back 
> > to the application; doesn't a read/write on a nonblocking device return 
> > EAGAIN if there's nothing to do?
> 
> Should a PR be opened?

Done: 56274 => http://www.freebsd.org/cgi/query-pr.cgi?pr=56274
-- 
Dan Langille : http://www.langille.org/