In article <20100506150045.ga...@marx.bitnet>, Jukka Ruohonen <jruoho...@iki.fi> wrote: >On Thu, May 06, 2010 at 02:48:32PM +0200, Joerg Sonnenberger wrote: >> On Thu, May 06, 2010 at 08:51:29AM +0000, David Holland wrote: >> > On Thu, May 06, 2010 at 08:14:08AM +0000, Jukka Ruohonen wrote: >> > > Correct the discussion about return values: fileno() may fail and >return -1. >> > > Note that in such cases the NetBSD implementation does not set errno to >> > > EBADF, hence diverging from the standard in this small detail. >> > >> > How is that not just a bug? >> >> -1 is a valid answer for not file-backed FILEs. I don't think it is an >> error. > >RETURN VALUE > > Upon successful completion, fileno() shall return the integer value of >the file descriptor associated with stream. Otherwise, the value -1 shall be >returned and errno set to indicate the error. > >ERRORS > > The fileno() function may fail if: > > [EBADF] > The stream argument is not a valid stream, or the stream is not > associated with a file. > >Isn't the above EBADF exactly what you are after?
Our stdio supports funopen() which has FILE *'s where fileno() == -1, but they work just fine... This should be documented. Perhaps set errno if it is indeed a bad file descriptor, and don't set it if it is a side-effect of funopen()? christos
