Re: [RFD] Combined fork-exec syscall.

[Werner Almesberger <wa@almesberger.net>]

Mark Grosberg wrote:
>    fmap[0] = in[0];                     /* STDIN  */
>    fmap[1] = out[1];                    /* STDOUT */
>    fmap[2] = open("/dev/null", O_RDWR); /* STDERR */
>    fmap[3] = -1;                        /* end    */
> 
>    p = nexec("/bin/cat",
>              null_argv,
>              NULL,
>              filmap);

How about

    fdrplc(3,fmap);
    exec("/bin/cat",...);

?

0) System call names must be short and cryptic :-)
1) Requiring the kernel to iterate over the array element by element
   in order to find out how big it is may be inefficient. Better to
   pass the length.
2) System call overhead is marginal, particularly in this case.
3) There may be other uses than exec(2), where a way for closeing
   all fds and getting a new set may be useful.

- Werner

-- 
  _________________________________________________________________________
 / Werner Almesberger, Buenos Aires, Argentina         wa@almesberger.net /
/_http://www.almesberger.net/____________________________________________/