配置系統常量
1、當檔案系統工作的時候檢查並配置這些喜好設定
檔案系統啟動並執行時候這些預設的值會適當的增加系統的安全性，但是在php或apache的底層單獨的為每各使用者開一個進程的時候，使用八進位的值永遠是正確的
FILE_READ_MODE 讀取檔案的模式
FILE_WRITE_MODE 寫入檔案的模式
DIR_READ_MODE 讀取目錄的模式
DIR_WRITE_MODE 寫入目錄的模式
2、檔案流模式
當我們使用fopen()/popen()的時候需要這些模式
define('FOPEN_READ', 'rb');
define('FOPEN_READ_WRITE', 'r+b');
define('FOPEN_WRITE_CREATE_DESTRUCTIVE', 'wb');
define('FOPEN_READ_WRITE_CREATE_DESTRUCTIVE', 'w+b');
define('FOPEN_WRITE_CREATE', 'ab');
define('FOPEN_READ_WRITE_CREATE', 'a+b');
define('FOPEN_WRITE_CREATE_STRICT', 'xb');
define('FOPEN_READ_WRITE_CREATE_STRICT', 'x+b');
檔案源碼：
複製代碼 代碼如下:
[php]
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/*
|--------------------------------------------------------------------------
| File and Directory Modes
|--------------------------------------------------------------------------
| These prefs 控制台、喜好設定 are used when checking and setting modes when working
| with the file system. The defaults are fine 罰款 on servers with proper
| security, but you may wish (or even need) to change the values in
| certain environments (Apache running a separate process for each
| user, PHP under CGI with Apache suEXEC, etc.). Octal values should
| always be used to set the mode correctly.
*/
define('FILE_READ_MODE', 0644);
define('FILE_WRITE_MODE', 0666);
define('DIR_READ_MODE', 0755);
define('DIR_WRITE_MODE', 0777);
/*
|--------------------------------------------------------------------------
| File Stream Modes 檔案流模式
|--------------------------------------------------------------------------
| These modes are used when working with fopen()/popen()
*/
define('FOPEN_READ', 'rb');
define('FOPEN_READ_WRITE', 'r+b');
define('FOPEN_WRITE_CREATE_DESTRUCTIVE', 'wb'); // truncates existing file data, use with care
define('FOPEN_READ_WRITE_CREATE_DESTRUCTIVE', 'w+b'); // truncates existing file data, use with care
define('FOPEN_WRITE_CREATE', 'ab');
define('FOPEN_READ_WRITE_CREATE', 'a+b');
define('FOPEN_WRITE_CREATE_STRICT', 'xb');
define('FOPEN_READ_WRITE_CREATE_STRICT', 'x+b');
/* End of file constants.php */
/* Location: ./application/config/constants.php */
