te.c

#include <unistd.h>
#include <termios.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include <errno.h>

struct termios orig_termios;

void die(const char *s) {
    perror(s);
    exit(1);
}

void disableRawMode() {
    if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &orig_termios) == -1) 
        die("tcsetattr");
}

void enableRawMode() {
    if(tcgetattr(STDIN_FILENO, &orig_termios) == -1)
        die("tcsetattr");
    atexit(disableRawMode);

    struct termios raw = orig_termios;
    raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
    raw.c_oflag &= ~(OPOST);
    raw.c_lflag &= ~(ECHO | ICANON | ISIG | IEXTEN);
    raw.c_cflag |= (CS8);
    
    raw.c_cc[VMIN] = 0;
    raw.c_cc[VTIME] = 1;

    if(tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw))
        die("tcsetattr");
}

int main() {
    enableRawMode();
    while(1) {
        char c = '\0'; 
        if(read(STDIN_FILENO, &c, 1) == -1 && errno != EAGAIN)
            die("read");
        if(iscntrl(c)) {
            printf("%d\r\n", c);
        } else {
            printf("%d ('%c')\r\n", c, c);
        }
        if(c == 'q') break;
    }
    return 0;
}