set_open_status

Corinna Vinschen corinna-cygwin@cygwin.com
Thu Feb 18 09:07:45 GMT 2021


On Feb 17 16:35, Ken Brown via Cygwin-developers wrote:
> Most fhandlers call set_open_status in their 'open' method before a
> successful return.  I just noticed that fhandler_fifo::open doesn't do this.
> I thought at first that it was an oversight on my part from when I
> overhauled the FIFO implementation, but I just checked fhandler_fifo.cc as
> of cygwin 2.9.0, and I don't see it there either.
> 
> Is there some reason this would be wrong for FIFOs?

I guess this was just an oversight.  It's certainly not fatal, given how
open_status is used exclusively by fhandler_base::reset_to_open_binmode()
in turn *only* called from setmode(fd, 0).  This is quite a bordercase.
Combined with FIFOs supporting only O_BINARY mode anyway...

It won't hurt to add the set_open_mode call to FIFOs but it won't change
anything, except avoiding to report O_TEXT mode after a call to
setmode(fd, 0).

Maybe it would be better to change fhandler_base::reset_to_open_binmode
instead.  Right now, if open_status hasn't been initialized, it prefers
O_TEXT over O_BINARY.  That's unfortunate, because it forces us to call
set_open_mode everywhere to make sure the mode is stored correctly for
this single, and seldom, invocation of setmode(fd, 0).  It would be nice
if set_open_mode would only be necessary on fhandlers supporting O_TEXT
at all.


Corinna


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