Log4php 使用心得

使用log4php 记录系统日志：

1、自动拦截php报出的错误，写日志

2、手动打印错误

set_error_handler('captureNormal',E_ERROR | E_PARSE);
set_exception_handler('captureException');
register_shutdown_function('captureShutdown');

自动拦截错误时，其中拦截captureShutDown中的处理不能写日志，进过调试发现log4php中有自己的错误处理函数，在错误处理函数中将写日志功能关闭了。

/**
 * Default constructor.
 * @param string $name Appender name
 */
public function __construct($name = '') {
    $this->name = $name;
    
    // Closes the appender on shutdown. Better than a destructor because
    // it will be called even if a fatal error occurs (destructor won't).
    register_shutdown_function(array($this, 'close'));
    
    if ($this->requiresLayout) {
        $this->layout = $this->getDefaultLayout();
    }
}

LoggerAppenderFile 继承与 LoggerAppendder

其中重写了close方法

public function close() {
    if($this->closed != true) {
        if($this->fp and $this->layout !== null) {
            if(flock($this->fp, LOCK_EX)) {
                fwrite($this->fp, $this->layout->getFooter());
                flock($this->fp, LOCK_UN);
            }
            fclose($this->fp);
        }
        $this->closed = true;
    }
}

调试中发现，调用close方法没有堆栈信息，猜想多半是使用了 register_shutdown_function