Listen and get keyboard input with nonblock way

get-keyboard-hit-nonblock.c

#ifdef __WIN32
#include <conio.h>
#include <stdio.h>

#else

#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>

int kbhit(void)
{
  struct termios oldt, newt;
  int ch;
  int oldf;

  tcgetattr(STDIN_FILENO, &oldt);
  newt = oldt;
  newt.c_lflag &= ~(ICANON | ECHO);
  tcsetattr(STDIN_FILENO, TCSANOW, &newt);
  oldf = fcntl(STDIN_FILENO, F_GETFL, 0);
  fcntl(STDIN_FILENO, F_SETFL, oldf | O_NONBLOCK);

  ch = getchar();
  tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
  fcntl(STDIN_FILENO, F_SETFL, oldf);
  if(ch != EOF) {
    ungetc(ch, stdin);
    return 1;
  }

  return 0;
}

#endif

char getKbhit()
{
  char ch;
  if (kbhit()){
    ch = getchar();
    return ch;
  } else {
    return -1;
  }
}

int main(void)
{
  while ('q' != getKbhit()) {
    printf("just print something if no 'q' press\n");
  }

  return 0;
}