Re: PATCH: pgbench - option to build using ppoll() for larger connection counts

On Wed, Nov 29, 2017 at 8:10 AM, Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr> wrote:
> My point is consistent with my other advice which is to hide the stuff in
> functions with identical (or compatible) signatures, so that the only place
> where it would differ would be in the functions, where greping would work.
>
> #ifdef USE_POLL
> // pool specific stuff
> #define SOME_TYPE v1_type (or typedef)
> void do_stuff(v1_type * stuff) { ... }
> ...
> #else /* default to SELECT */
> // select specific stuff
> #define SOME_TYPE v2_type (idem)
> void do_stuff(v2_type * stuff) { ... }
> ...
> #endif
>
> Then later the code is not specific to poll or select, eg:
>
> SOME_TYPE mask;
> do_stuff(mask);
> do_other_stuff(...);
> if (is_ready(mask, ...)) { ... }

Yeah, that sort of style would be OK with me. But I wouldn't like:

struct blah {
#ifdef FOO
int doohicky;
#else
char *doohicky;
};

...because now any place in the code where you see "doohicky" you
don't immediately know whether it's an int or a char *

--
Robert Haas
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