(Fwd) Re: SCSI tape data loss

Dan Langille dan at langille.org
Sun Aug 31 17:34:20 PDT 2003


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?
-- 
Dan Langille : http://www.langille.org/



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