linux c++ libev official example show redundant console behavior

I just tried the official example of libev, like below. After compiling and running, I see once I input anything from stdin, the event is triggered, no problem. But what I inputed is still treated as solid input and then appear on my console. My question is: is there a way to avoid this console input from being prompted to console, and just like libev to catch and store it?

Any way in libev can do this?

I paste the official example here:

    // a single header file is required
    #include <ev.h>

    #include <stdio.h> // for puts

    // every watcher type has its own typedef'd struct
    // with the name ev_TYPE
    ev_io stdin_watcher;
    ev_timer timeout_watcher;

    // all watcher callbacks have a similar signature
    // this callback is called when data is readable on stdin
    static void
    stdin_cb (EV_P_ ev_io *w, int revents)
    {
      puts ("stdin ready");
      // for one-shot events, one must manually stop the watcher
      // with its corresponding stop function.
      ev_io_stop (EV_A_ w);

      // this causes all nested ev_run's to stop iterating
      ev_break (EV_A_ EVBREAK_ALL);
    }

    // another callback, this time for a time-out
    static void
    timeout_cb (EV_P_ ev_timer *w, int revents)
    {
      puts ("timeout");
      // this causes the innermost ev_run to stop iterating
      ev_break (EV_A_ EVBREAK_ONE);
    }

    int
    main (void)
    {
      // use the default event loop unless you have special needs
      struct ev_loop *loop = EV_DEFAULT;

      // initialise an io watcher, then start it
      // this one will watch for stdin to become readable
      ev_io_init (&stdin_watcher, stdin_cb, /*STDIN_FILENO*/ 0, EV_READ);
      ev_io_start (loop, &stdin_watcher);

      // initialise a timer watcher, then start it
      // simple non-repeating 5.5 second timeout
      ev_timer_init (&timeout_watcher, timeout_cb, 5.5, 0.);
      ev_timer_start (loop, &timeout_watcher);

      // now wait for events to arrive
      ev_run (loop, 0);

      // break was called, so exit
      return 0;
    }

Answer

I assume you mean the echoing of what you write? It’s the default behavior of terminal program. You can use termios functions and flags to disable echoing. Remember to enable it before exiting your program though.

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Answer