Re: gdb/remote - I/O

[Andrew Cagney <ac131313 at cygnus dot com>]

Mark Salter wrote:

> Andrew,
> 
> >From a target-side perspective, I'd like to see this as something like:
> 
> -> c (continue)
> >       <- T<sigint> (1)
> -> i<input>
> >       <- OK
> -> c (continue)
> >       .....
> 
> (1) Also extended somehow to include indication that target wants
>     input and the max size of the input desired.

Wants or is able to accept input?
What should GDB do if there is no input available?

> This eliminates the need for interrupt/Ctrl-C support in the stub.
> I've certainly written stubs for boards that didn't have interrupts
> on the debug channel and boards which used an NMI button on the board
> for that purpose.

Good point.

> It also explicitly tells gdb whether or not the stub supports input
> and provides some flow control by having the target tell gdb how
> much input it can handle.
> 
> Finally, for stubs which do support input, not all apps will want
> to use that mechanism and pushing data from the gdb side would
> be disruptive for such apps.

So you're suggesting a polling mechanism?

	Andrew