Re: Introduce posix_spawn

[Eric Blake]

Adding gnulib:

On 09/06/2018 11:37 PM, Barath Aron wrote:
> On 9/7/18 4:54 AM, Dale R. Worley wrote:
> > Couldn't you change the w.d. to the correct target, spawn, and then
> > change the w.d. back?
> Yes, one could do this.
> > Alternatively, one could direct the spawned process to run a program
> > that would set the working directory to, say, the first argument, and
> > then use the remaining arguments to run/fork/spawn the target program.
> Do you know systems that have this program? What is the name of this 
> utility program?
> > Indeed, I would expect Threos to have a system program to do exactly
> > this, since other people must have seen the same problem.
>
> Actually, this particular problem can be easily solved on Threos, 
> because the posix_spawn() API offers a function for this:
> int posix_spawn_file_actions_addchdir_np(posix_spawn_file_actions_t* 
> __restrict file_actions, const char* __restrict path);
>
> Note the "np" at the end, it means "non portable". I also found 
> references on Oracle's webpage [1].

It's useful enough that we may want to add support for this in gnulib, 
whether or not other systems pick up on it.  (gnulib is already able to 
overcome a lot of shortcomings in various platforms' posix_spawn)

> Aron
>
>
> [1] 
> https://docs.oracle.com/cd/E86824_01/html/E54766/posix-spawn-file-actions-addchdir-np-3c.html 

--
Eric Blake, Principal Software Engineer
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