[PATCH v3 1/1] waitid: Add support for waiting for the current process group

[Christian Brauner]

On Wed, Aug 14, 2019 at 06:15:17PM +0200, Christian Brauner wrote:
> On Wed, Aug 14, 2019 at 06:09:17PM +0200, Oleg Nesterov wrote:
> > On 08/14, Christian Brauner wrote:
> > >
> > > and a signal could come in between the system call that
> > > retrieved the process gorup and the call to waitid that changes the
> >                         ^^^^^
> > > current process group.
> > 
> > I noticed this typo only because I spent 2 minutes or more trying to
> > understand this sentence ;) But yes, a signal handler or another thread
> 
> I'll try to rewrite it. :)

Ok, here's what I changed it to:

It was recently discovered that the linux version of waitid is not a
superset of the other wait functions because it does not include
support for waiting for the current process group. This has two
downsides:
1. An extra system call is needed to get the current process group.
2. After the current process group is received and before it is passed
   to waitid a signal could arrive causing the current process group to change.

Christian