(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
readline_callback_handler_install(string $prompt, callable $callback): true
Sets up a readline callback interface then prints prompt and immediately returns. Calling this function twice without removing the previous callback interface will automatically and conveniently overwrite the old interface.
The callback feature is useful when combined with stream_select() as it allows interleaving of IO and user input, unlike readline().
promptThe prompt message.
callback The callback function takes one parameter; the user input returned.
Always returns true.
Example #1 Readline Callback Interface Example
<?php
function rl_callback($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";
?>
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https://www.php.net/manual/en/function.readline-callback-handler-install.php