Re: [libgpiod] feature request: output state read and sustain

[Andy Shevchenko <andy.shevchenko@xxxxxxxxx>]

On Wed, Jun 29, 2022 at 12:48 PM Kent Gibson <warthog618@xxxxxxxxx> wrote:
> On Wed, Jun 29, 2022 at 12:27:13PM +0200, Andy Shevchenko wrote:
> > On Wed, Jun 29, 2022 at 11:27 AM Jiří Prchal <jiri.prchal@xxxxxxxxxxx> wrote:

...

> > Do not use shell. Use proper programming language that may give you an
> > easier way of handling this, i.e. _context_. Shell tools are
> > _context-less_ and here is the problem you are trying to solve, but
> > from the wrong end.
>
> Actually my proposed gpioset for v2 will support running interactively
> so it can maintain context and be driven from shell - for cases where
> basic scripting will suffice.

Dunno if it's the right direction and if I missed any (additional) discussion.
As far as I remember the idea was to introduce DBus aware daemon that
should handle the context of the line and at the same time consider security
implications. Allowing shell to be context-aware is a hidden mine
field. What will happen if the script/user forgets to move the line to
the proper state and the chip will drain a lot of current? So, at
least PM concerns just popped up immediately to my mind. What else can
be problematic? So, I dunno, it's a good idea to allow shell to leave
a line in some state when the user actually doesn't care about it
anymore. At the bare minimum this mustn't be default behaviour.

-- 
With Best Regards,
Andy Shevchenko