Re: Introduce posix_spawn

[Eric Blake]

On 09/08/2018 02:24 AM, Bernhard Voelker wrote:
> On 09/08/18 00:15, Eric Blake wrote:
> > Adding posix_spawn_file_actions_addchdir() is what avoids the need to
> > lock in the parent, because now you do:
>
> A thought WRT the naming: while ..._addopen() can be called for more file
> descriptors, there's only one working directory for the spawned process.
> Therefore I suggest to simply call it posix_spawn_file_actions_chdir(),
> i.e., without the "add" in its name.
> To "remove" this from the posix_spawn_file_actions again (before calling
> posix_spawn, of course), one could also simply use
>     posix_spawn_file_actions_chdir(NULL);
>
> WDYT?

I'm not a fan of it.  Remember, we already have 
posix_spawn_file_actions_addclose().

The _add name is representing the fact that you are adding to the 
growing list of file_actions to be applied later.

You can't undo a chdir; but you CAN do multiple chdir to affect 
intermediate state, where only the last chdir determines where the 
current working directory of the child will be.

And the fact that Solaris already has 
posix_spawn_file_actions_addchdir_np() is pretty strong precedent for 
keeping the name _addchdir, rather than picking a different name (we're 
dropping the _np suffix as part of standardizing things, since _np means 
non-portable but a standardized version is portable - but nothing else 
really needs to change from what has already been implemented in other 
platforms).

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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