PATCH: Get rid of superfluous dup() and close() calls.

Martin Wilck Martin.Wilck at Fujitsu-Siemens.com
Mon Feb 3 02:43:14 CST 2003


Am Fre, 2003-01-31 um 22.37 schrieb Alexandre Julliard:

> I think it's cleaner to return a dup of the fd instead of relying on
> the fact that the fd is cached internally. This may not always be the
> case, and it's better to risk an fd leak than to risk invalidating the
> cached value in case someone closes the fd when they shouldn't.

I see your point, but I don't see the risk you're talking about.

The new coding rule (after removing the dup) is very simple: 

   ** Never close() a Unix fd that you haven't open()d or dup()d
   ** yourself.

Actually, one could formulate it more clearly:

   ** Never call close() unless you really know what you're doing.

That is easy to understand for everybody, I reckon. I think it is much
more likely that a programmer forgets a close() call than that he
erroneously writes one, especially because it is pretty hard to even
find the hidden dup() that creates all these fd's. When I was new to
wine I guess it took me least a week to understand why the close() calls
appeared everywhere.

The current rule is much more complex. Especially with asynchronous IO 
it becomes *very* hard to track the open fd's.

Please rethink your position on this subject.

Martin

-- 
Martin Wilck                Phone: +49 5251 8 15113
Fujitsu Siemens Computers   Fax:   +49 5251 8 20409
Heinz-Nixdorf-Ring 1	    mailto:Martin.Wilck at Fujitsu-Siemens.com
D-33106 Paderborn           http://www.fujitsu-siemens.com/primergy








More information about the wine-devel mailing list