readline_callback_handler_install
(PHP 5 >= 5.1.0, PHP 7)
readline_callback_handler_install — Initializes the readline callback interface and terminal, prints the prompt and returns immediately
Описание
Sets up a readline callback interface then prints
prompt and immediately returns.
Calling this function twice without removing the previous
callback interface will automatically and conveniently overwrite the old
interface.
The callback feature is useful when combined with stream_select() as it allows interleaving of IO and user input, unlike readline().
Список параметров
-
prompt -
The prompt message.
-
callback -
The
callbackfunction takes one parameter; the user input returned.
Возвращаемые значения
Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки.
Примеры
Пример #1 Readline Callback Interface Example
<?php
function rl_callback($ret)
{
global $c, $prompting;
echo "You entered: $ret\n";
$c++;
if ($c > 10) {
$prompting = false;
readline_callback_handler_remove();
} else {
readline_callback_handler_install("[$c] Enter something: ", 'rl_callback');
}
}
$c = 1;
$prompting = true;
readline_callback_handler_install("[$c] Enter something: ", 'rl_callback');
while ($prompting) {
$w = NULL;
$e = NULL;
$n = stream_select($r = array(STDIN), $w, $e, null);
if ($n && in_array(STDIN, $r)) {
// read a character, will call the callback when a newline is entered
readline_callback_read_char();
}
}
echo "Prompting disabled. All done.\n";
?>
Смотрите также
- readline_callback_handler_remove() - Removes a previously installed callback handler and restores terminal settings
- readline_callback_read_char() - Reads a character and informs the readline callback interface when a line is received
- stream_select() - Запускает эквивалент системного вызова select() на заданных массивах потоков с таймаутом, указанным параметрами tv_sec и tv_usec
Коментарии
To read byte wise and multi line you can check the line_buffer from readline_info:
<?php
function read(int $count, string $prompt = null): string
{
$previous = '';
readline_callback_handler_install($prompt ?? " \e[D", function ($str) use (&$previous) {
$previous .= $str . PHP_EOL;
});
do {
$r = array(STDIN);
$n = stream_select($r, $w, $e, null);
if ($n && in_array(STDIN, $r)) {
readline_callback_read_char();
$str = $previous . readline_info('line_buffer');
}
} while (mb_strlen($str) < $count); // use strlen if you need the exact byte count
readline_callback_handler_remove();
return $str;
}