1 /* 2 C non-blocking keyboard input 3 http://stackoverflow.com/questions/448944/c-non-blocking-keyboard-input 4 */ 5 6 #include <stdlib.h> 7 #include <string.h> 8 #include <sys/select.h> 9 #include <termios.h> 10 #include <unistd.h> 11 12 struct termios orig_termios; 13 14 void reset_terminal_mode() 15 { 16 tcsetattr(0, TCSANOW, &orig_termios); 17 } 18 19 void set_conio_terminal_mode() 20 { 21 struct termios new_termios; 22 23 /* take two copies - one for now, one for later */ 24 tcgetattr(0, &orig_termios); 25 memcpy(&new_termios, &orig_termios, sizeof(new_termios)); 26 27 /* register cleanup handler, and set the new terminal mode */ 28 atexit(reset_terminal_mode); 29 cfmakeraw(&new_termios); 30 new_termios.c_oflag |= OPOST; 31 tcsetattr(0, TCSANOW, &new_termios); 32 } 33 34 int kbhit() 35 { 36 struct timeval tv = { 0L, 0L }; 37 fd_set fds; 38 FD_ZERO(&fds); // not in original posting to stackoverflow 39 FD_SET(0, &fds); 40 return select(1, &fds, NULL, NULL, &tv); 41 } 42 43 int getch() 44 { 45 int r; 46 unsigned char c; 47 if ((r = read(0, &c, sizeof(c))) < 0) { 48 return r; 49 } else { 50 return c; 51 } 52 } 53 54 #if 0 55 int main(int argc, char *argv[]) 56 { 57 set_conio_terminal_mode(); 58 59 while (!kbhit()) { 60 /* do some work */ 61 } 62 (void)getch(); /* consume the character */ 63 } 64 #endif 65
