I have a program which is spewing junk to std::cout from all over the
place.  I would like to be able to catch a keypress without blocking,
and so I have used ncurses to do so.  Unfortunately using the wgetch()
function seems to cause a screen clear on each read, which results in
flicker in the application.  clearok(w,FALSE) does not seem to work.
My code is:

WINDOW* w = initscr();
nodelay(w,true);

bool q(false);
while(!q)
{
std::cout << "Print junk!\n";

clearok(w,FALSE);
wrefresh(w);
int kk=wgetch(w);
endwin();

switch(kk)
{
case 'q': q=true;
break;
case -1:
break;
default:
std::cout << "A ket!\n";
}

sleep(1);

}

Is there any way to eliminate the flicker?  Is the above code
incorrect?

Thank you for any/all help.

don

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>I would like to be able to catch a keypress without blocking,
>and so I have used ncurses to do so.  >Unfortunately using the wgetch()
>function seems to cause a screen clear on each read

I do not think that you can use [n]curses functions without letting
curses control the screen.

In similar situations, I use a shell skript using stty and trap to
start the program in raw mode.

Outline (without check), consult man pages of your system!

#!/bin/sh
trap '[ -f .saved ] && stty .saved ; rm -f .saved; exit'  1 2 3 15
# save setting
stty -g >.saved
# no echo, deliver each char (system dependent!!)
stty -echo raw cbreak
yourprogram "$@"
EXITCODE=$?
stty .saved
exit $EXITCODE

The you can use getchar etc. in your program. Note that the skript also
preserves the exit code.
Hubble.

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