Re: [gpsd-dev] [PATCH] Remove duplicate <sys/socket.h> include.

[Fred Wright]

On Mon, 7 Mar 2016, Rob Norris wrote:

> TESTED
> 'scons build-all check' with and without qt passes.
> ---
>  libgps_sock.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/libgps_sock.c b/libgps_sock.c
> index 169a900..d056515 100644
> --- a/libgps_sock.c
> +++ b/libgps_sock.c
> @@ -17,7 +17,6 @@
>  #include <sys/types.h>
>  #include <sys/stat.h>
>  #include <sys/select.h>
> -#include <sys/socket.h>
>  #include <unistd.h>
>
>  #ifndef USE_QT
> --
> 2.7.0
>
>
>

Well, it certainly doesn't need to include it twice. :-)

But the real question is which definition should be removed.  It's good
practice to always directly include any header that's directly used,
regardless of whether it's also indirectly included via some other header
(and of course the duplicate inclusion is filtered out by the guard
check).  So if the code makes any use of socket.h definitions in the
USE_QT case, it's preferable to keep the unconditional include and remove
the conditional one.  If it *only* uses Qt's socket definitions in the
USE_QT case, then removing the unconditional include is fine.

You can't tell the difference by checking for build errors; it's just that
relying on indirect includes is more fragile.

Fred Wright