C warning that I can't seem to track down

[Tim Writer]

Lennart Sorensen <lsorense-1wCw9BSqJbv44Nm34jS7GywD8/FfD2ys at public.gmane.org> writes:

> On Tue, Aug 08, 2006 at 09:30:07AM -0400, bob wrote:
> > In newer versions of the GCC compiler the block of C code:
> > 
> > int length;
> 
> You didn't specify, so perhaps it is a signed int.
> 
> > ...
> > 
> > if(getsockname(s, (struct sockaddr *)&sin, &length))
> > 
> > gives a warning below
> > 
> > socketUtils.c:259: warning: pointer targets in passing argument 3 of 
> > 'getsockname' differ in signedness
> > 
> > 
> > I tracked it down to a define called "socklen_t".    Damned if I can find 
> > where that is defined.
> > 
> > Any help would be appreciated.   Thanks.
> 
> socklen_t is defined as an unsigned 32 bit value.  Try making your int
> unsigned as well.

The correct solution is to define length as:

    socklen_t   length;

as pointed out by an earlier poster. Otherwise, if sizeof(socklen_t) is not
the same as sizeof(int), casting &length to a pointer to socklen_t will be
disastrous.

Types like socklen_t are your friends. Use them to help you.

-- 
tim writer <tim-s/rLXaiAEBtBDgjK7y7TUQ at public.gmane.org>                                  starnix inc.
647.722.5301                                      toronto, ontario, canada
http://www.starnix.com              professional linux services & products
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