Re: [Help-bash] How to determine the parent's parent (Was: Re: Where does $TERM come from?)

[Chris F.A. Johnson]

On Sun, 21 Jun 2015, Chris F.A. Johnson wrote:

> On Sun, 21 Jun 2015, Dennis Williamson wrote:
>
> > On Sun, Jun 21, 2015 at 3:57 PM, Andrew Miller <address@hidden> wrote:
> >
> > > Eduardo A. Bustamante López <address@hidden> writes:
> > > > If you want to explore the process tree, use a tool like ps:
> > >
> > > I'm looking to replace the "case $TERM in..." statement in my bashrc with
> > > something more fine-grained.
> > >
> > > Since it runs every time bash is launched, and my machine is a 15-year-old
> > > thinkpad, I'd prefer not to call an external program like ps. That adds a
> > > lot
> > > of overhead.
> >
> >
> > On a system with /proc:
> >
> > stat=($(</proc/$$/stat))    # create an array
> > ppid=${stat[3]}             # get the fourth field
>
>   Command substitution is almost as slow as an external command and
>   unnecessary:
>
> read -a stat < /proc/$$/stat

   Or:

read a b c ppid e <  /proc/$$/stat

   Or:

echo "$PPID"

--
Chris F.A. Johnson, <http://cfajohnson.com>