[Caml-list] catch keypressed

[Caml-list] catch keypressed

[Vincent Barichard]

Hello,

I would like to catch the hit of a key without being in graphic
mode. Something like :

while not keypressed() do
  print_string "Hit a key";
done;

Is a fonction of this kind exists in CAML ??
And if it doesn't exist, is there a way to simulate its effect ??
The read_int fonction blocks until user enter a value so it is not
suitable for my problem.

thanks for your help

Vincent


Vincent Barichard
Métaheuristiques et Optimisation Combinatoire
Faculté des Sciences d'Angers
Tel : 02 41 73 52 06
-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners

Re: [Caml-list] catch keypressed

[Remi VANICAT]

Vincent Barichard <barichar@info.univ-angers.fr> writes:

> Hello,
> 
> I would like to catch the hit of a key without being in graphic
> mode. Something like :
> 
> while not keypressed() do
>   print_string "Hit a key";
> done;
> 
> Is a fonction of this kind exists in CAML ??
> And if it doesn't exist, is there a way to simulate its effect ??
> The read_int fonction blocks until user enter a value so it is not
> suitable for my problem.

the read_line function wait until return is pressed. It is not exactly
what you want, but it's often enough.
-- 
Rémi Vanicat
vanicat@labri.u-bordeaux.fr
http://dept-info.labri.u-bordeaux.fr/~vanicat
-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners

Re: [Caml-list] catch keypressed

[Gerd Stolpmann]

On 2002.05.02 12:23 Vincent Barichard wrote:
> 
> Hello,
> 
> I would like to catch the hit of a key without being in graphic
> mode. Something like :
> 
> while not keypressed() do
>   print_string "Hit a key";
> done;
> 
> Is a fonction of this kind exists in CAML ??
> And if it doesn't exist, is there a way to simulate its effect ??
> The read_int fonction blocks until user enter a value so it is not
> suitable for my problem.
> 
> thanks for your help
> 
> Vincent

Quite simple: Turn the "canonical mode" of stdin off, and keypresses
are reported immediately:

open Unix;;
let waitkey() =
  let m = tcgetattr stdin in
  tcsetattr stdin TCSAFLUSH { m with c_icanon = false };  
  let s = String.create 1 in
  ignore(read stdin s 0 1);
  tcsetattr stdin TCSAFLUSH m;
  s.[0]
;;

Maybe you also want to turn off echo mode (c_echo=false). Changing the
terminal mode is dangerous, because it is a property of the terminal
emulator, and is not automatically reset if the program stops for any
reason. Because of this, it is a good idea to register an at_exit function
that restores the terminal mode when the program terminates, and to catch
also the various signals that might lead to termination.

And if the cursor has vanished: type "stty sane" to reset the terminal
modes from the shell.

Gerd
-- 
----------------------------------------------------------------------------
Gerd Stolpmann      Telefon: +49 6151 997705 (privat)
Viktoriastr. 45             
64293 Darmstadt     EMail:   gerd@gerd-stolpmann.de
Germany                     
----------------------------------------------------------------------------
-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners

Re: [Caml-list] catch keypressed

[Vincent Barichard]

Thanks for your help, I'll use the following function which works very
well :

 open Unix;;
 let waitkey() =
   let m = tcgetattr stdin in
   tcsetattr stdin TCSANOW { m with c_vmin = 0; c_icanon = false };
   let s = String.create 1 in
   ignore(read stdin s 0 1);
   tcsetattr stdin TCSAFLUSH m;
   s.[0]
 ;;

Thanks again.

Vincent

On Thu, 2 May 2002, Gerd Stolpmann wrote:

>
> On 2002.05.02 12:23 Vincent Barichard wrote:
> >
> > Hello,
> >
> > I would like to catch the hit of a key without being in graphic
> > mode. Something like :
> >
> > while not keypressed() do
> >   print_string "Hit a key";
> > done;
> >
> > Is a fonction of this kind exists in CAML ??
> > And if it doesn't exist, is there a way to simulate its effect ??
> > The read_int fonction blocks until user enter a value so it is not
> > suitable for my problem.
> >
> > thanks for your help
> >
> > Vincent
>
> Quite simple: Turn the "canonical mode" of stdin off, and keypresses
> are reported immediately:
>
> open Unix;;
> let waitkey() =
>   let m = tcgetattr stdin in
>   tcsetattr stdin TCSAFLUSH { m with c_icanon = false };
>   let s = String.create 1 in
>   ignore(read stdin s 0 1);
>   tcsetattr stdin TCSAFLUSH m;
>   s.[0]
> ;;
>
> Maybe you also want to turn off echo mode (c_echo=false). Changing the
> terminal mode is dangerous, because it is a property of the terminal
> emulator, and is not automatically reset if the program stops for any
> reason. Because of this, it is a good idea to register an at_exit function
> that restores the terminal mode when the program terminates, and to catch
> also the various signals that might lead to termination.
>
> And if the cursor has vanished: type "stty sane" to reset the terminal
> modes from the shell.
>
> Gerd
> --
> ----------------------------------------------------------------------------
> Gerd Stolpmann      Telefon: +49 6151 997705 (privat)
> Viktoriastr. 45
> 64293 Darmstadt     EMail:   gerd@gerd-stolpmann.de
> Germany
> ----------------------------------------------------------------------------
> -------------------
> To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
> Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
> Beginner's list: http://groups.yahoo.com/group/ocaml_beginners
>

Vincent Barichard
Métaheuristiques et Optimisation Combinatoire
Faculté des Sciences d'Angers
Tel : 02 41 73 52 06
-------------------
To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr
Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/
Beginner's list: http://groups.yahoo.com/group/ocaml_beginners