Function read_key_without_echo

compat/terminal.c:534–582

}

int read_key_without_echo(struct strbuf *buf)
{
	static int warning_displayed;
	int ch;

	if (warning_displayed || enable_non_canonical(SAVE_TERM_STDIN) < 0) {
		if (!warning_displayed) {
			warning("reading single keystrokes not supported on "
				"this platform; reading line instead");
			warning_displayed = 1;
		}

		return strbuf_getline(buf, stdin);
	}

	strbuf_reset(buf);
	ch = getchar();
	if (ch == EOF) {
		restore_term();
		return EOF;
	}
	strbuf_addch(buf, ch);

	if (ch == '\033' /* ESC */) {
		/*
		 * We are most likely looking at an Escape sequence. Let's try
		 * to read more bytes, waiting at most half a second, assuming
		 * that the sequence is complete if we did not receive any byte
		 * within that time.
		 *
		 * Start by replacing the Escape byte with ^[ */
		strbuf_splice(buf, buf->len - 1, 1, "^[", 2);

		/*
		 * Query the terminal capabilities once about all the Escape
		 * sequences it knows about, so that we can avoid waiting for
		 * half a second when we know that the sequence is complete.
		 */
		while (!is_known_escape_sequence(buf->buf)) {
			ch = getchar_with_timeout(500);
			if (ch == EOF)
				break;
			strbuf_addch(buf, ch);
		}
	}

	restore_term();
	return 0;
}

#else