keyb.c

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/*
kbhit() and getch() for Linux/UNIX
Chris Giese <geezer@execpc.com> http://my.execpc.com/~geezer
*/

#ifdef linux
    #include <sys/time.h> /* struct timeval, select() */
    #include <termios.h> /* tcgetattr(), tcsetattr() */
    #include <stdlib.h> /* atexit(), exit() */
    #include <unistd.h> /* read() */
    #include <stdio.h> /* printf() */
    #include <string.h> /* memcpy() */

#define CLEARSCR "clear"

static struct termios g_old_kbd_mode;

/*****************************************************************************/
static void cooked(void)
{
        tcsetattr(0, TCSANOW, &g_old_kbd_mode);
}

static void raw(void)
{
        static char init;

        struct termios new_kbd_mode;

        if(init)
                return;
/* put keyboard (stdin, actually) in raw, unbuffered mode */
        tcgetattr(0, &g_old_kbd_mode);
        memcpy(&new_kbd_mode, &g_old_kbd_mode, sizeof(struct termios));
        new_kbd_mode.c_lflag &= ~(ICANON | ECHO);
        new_kbd_mode.c_cc[VTIME] = 0;
        new_kbd_mode.c_cc[VMIN] = 1;
        tcsetattr(0, TCSANOW, &new_kbd_mode);
/* when we exit, go back to normal, "cooked" mode */
        atexit(cooked);

        init = 1;
}

/*****************************************************************************/
/*  SLEEP  */
/*****************************************************************************/
void Sleep(int t) {
    usleep( t*1000 );
}

/*****************************************************************************/
/*  GETCH  */
/*****************************************************************************/
int getch(void)
{
        unsigned char temp;

        raw();
    /* stdin = fd 0 */
        if(read(0, &temp, 1) != 1)
                return 0;
        return temp;

}


/*****************************************************************************/
/*  KBHIT  */
/*****************************************************************************/
int kbhit()
{

        struct timeval timeout;
        fd_set read_handles;
        int status;

        raw();
    /* check stdin (fd 0) for activity */
        FD_ZERO(&read_handles);
        FD_SET(0, &read_handles);
        timeout.tv_sec = timeout.tv_usec = 0;
        status = select(0 + 1, &read_handles, NULL, NULL, &timeout);
        if(status < 0)
        {
                printf("select() failed in kbhit()\n");
                exit(1);
        }
    return (status);
}


#else  // Windows

    #include <conio.h>
#define CLEARSCR "cls"
#endif