How can I read single characters from the terminal?

How can I read single characters from the terminal?




How can I read single characters from the terminal? My program is always
waiting for the user to press RETURN.




Terminals are usually in canonical mode, where input is read in lines
after it is edited. You may set this into non-canonical mode, where you
set how many characters should be read before input is given to your
program. You also may set the timer in non-canonical mode terminals to
0, this timer flushs your buffer at set intervals. By doing this, you
can use getc() to grab the key pressed immediately by the
user. We use tcgetattr() and tcsetattr() both of which are
defined by POSIX to manipulate the termios structure. 





#include <stdlib.h>


#include <stdio.h>





#include <termios.h>


#include <string.h>





static struct termios stored_settings;





void set_keypress(void)


{


    struct termios new_settings;





    tcgetattr(0,&stored_settings);





    new_settings = stored_settings;





    /* Disable canonical mode, and set buffer size to 1 byte */


    new_settings.c_lflag &= (~ICANON);


    new_settings.c_cc[VTIME] = 0;


    new_settings.c_cc[VMIN] = 1;





    tcsetattr(0,TCSANOW,&new_settings);


    return;


}





void reset_keypress(void)


{


    tcsetattr(0,TCSANOW,&stored_settings);


    return;


}





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