# pcntl_signal_get_handler

(PHP 7 >= 7.1.0)

pcntl_signal_get_handler — Get the current handler for specified signal

### 说明

pcntl_signal_get_handler ( int `$signo` ) : mixed

The pcntl_signal_get_handler() function will get the current handler for the specified `signo`.

### 参数

`signo`

  The signal number.

### 返回值

This function may return an integer value that refers to `SIG_DFL` or `SIG_IGN`. If you set a custom handler a string value containing the function name is returned.

### 更新日志

版本 | 说明
--- | ---
7.1.0 | pcntl_signal_get_handler() has been added.

### 范例

Example #1 pcntl_signal_get_handler() example

    <?php
    var_dump(pcntl_signal_get_handler(SIGUSR1)); // Outputs: int(0)

    function pcntl_test($signo) {}
    pcntl_signal(SIGUSR1, 'pcntl_test');
    var_dump(pcntl_signal_get_handler(SIGUSR1)); // Outputs: string(10) "pcntl_test"

    pcntl_signal(SIGUSR1, SIG_DFL);
    var_dump(pcntl_signal_get_handler(SIGUSR1)); // Outputs: int(0)

    pcntl_signal(SIGUSR1, SIG_IGN);
    var_dump(pcntl_signal_get_handler(SIGUSR1)); // Outputs: int(1)
    ?>

### 参见

- pcntl_signal() - 安装一个信号处理器