(PHP 5 >= 5.1.0, PHP 7, PHP 8)
readline_callback_handler_install — Initializes the readline callback interface and terminal, prints the prompt and returns immediately
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() .
promptThe prompt message.
callback
The callback function takes one parameter; the
user input returned.
Always returns true .
Example #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";
?>
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;
}