readline_callback_handler_install

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

readline_callback_handler_install — 初始化 readline 回调接口和终端，然后打印提示并立即返回

说明

readline_callback_handler_install(string $prompt, callable $callback): bool

设置 readline 回调接口然后打印 prompt 并立即返回。在不移除旧的回调接口的情况下再次调用此函数，将自动覆盖旧接口。

与 stream_select() 结合使用时，回调功能很有用，因为允许 IO 和用户输入交互，这与 readline() 不同。

参数

prompt: 提示信息。
callback: callback 函数接受一个参数；返回用户输入。

返回值

成功时返回 true，或者在失败时返回 false。

示例

示例 #1 Readline 回调接口示例

<?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";
?>

参见

readline_callback_handler_remove() - 移除之前已安装的回调函数句柄并且恢复终端设置
readline_callback_read_char() - 当一个行被接收时读取一个字符并且通知 readline 回调接口
stream_select() - Runs the equivalent of the select() system call on the given arrays of streams with a timeout specified by seconds and microseconds

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thflori ¶

6 years ago

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;
}