CodeIgniter框架源码学习之系统常量定义文件--constants.php

文件位置: ./application/config/constants.php
文件内容较少直接上代码,解释
defined('BASEPATH') OR exit('No direct script access allowed');

/*
|--------------------------------------------------------------------------
| Display Debug backtrace
|--------------------------------------------------------------------------
|
| If set to TRUE, a backtrace will be displayed along with php errors. If
| error_reporting is disabled, the backtrace will not display, regardless
| of this setting
| 如果设置成true,debug轨迹(backtrace)将会和php错误一起显示,如果error_reporting是不展示的,则debug轨迹(backtrace)也将不会展示,可以忽略这个设置
|
*/
defined('SHOW_DEBUG_BACKTRACE') OR define('SHOW_DEBUG_BACKTRACE', TRUE);

/*
|--------------------------------------------------------------------------
| File and Directory Modes
|--------------------------------------------------------------------------
|
| These prefs are used when checking and setting modes when working
| with the file system. The defaults are fine 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.
| 当文件系统工作的时候检查并配置这些首选项;文件系统运行的时候这些默认的值会适当的增加系统的安全性,但是在php或apache的底层单独的为每各用户开一个进程的时候,使用八进制的值永远是正确的
*/
defined('FILE_READ_MODE') OR define('FILE_READ_MODE', 0644);
defined('FILE_WRITE_MODE') OR define('FILE_WRITE_MODE', 0666);
defined('DIR_READ_MODE') OR define('DIR_READ_MODE', 0755);
defined('DIR_WRITE_MODE') OR define('DIR_WRITE_MODE', 0755);

/*
|--------------------------------------------------------------------------
| File Stream Modes
|--------------------------------------------------------------------------
|
| These modes are used when working with fopen()/popen()
| 文件流模式 当我们使用fopen()/popen()的时候需要这些模式
*/
defined('FOPEN_READ') OR define('FOPEN_READ', 'rb');
defined('FOPEN_READ_WRITE') OR define('FOPEN_READ_WRITE', 'r+b');
defined('FOPEN_WRITE_CREATE_DESTRUCTIVE') OR define('FOPEN_WRITE_CREATE_DESTRUCTIVE', 'wb'); // truncates existing file data, use with care
defined('FOPEN_READ_WRITE_CREATE_DESTRUCTIVE') OR define('FOPEN_READ_WRITE_CREATE_DESTRUCTIVE', 'w+b'); // truncates existing file data, use with care
defined('FOPEN_WRITE_CREATE') OR define('FOPEN_WRITE_CREATE', 'ab');
defined('FOPEN_READ_WRITE_CREATE') OR define('FOPEN_READ_WRITE_CREATE', 'a+b');
defined('FOPEN_WRITE_CREATE_STRICT') OR define('FOPEN_WRITE_CREATE_STRICT', 'xb');
defined('FOPEN_READ_WRITE_CREATE_STRICT') OR define('FOPEN_READ_WRITE_CREATE_STRICT', 'x+b');

/*
|--------------------------------------------------------------------------
| Exit Status Codes
|--------------------------------------------------------------------------
|
| Used to indicate the conditions under which the script is exit()ing.
| While there is no universal standard for error codes, there are some
| broad conventions. Three such conventions are mentioned below, for
| those who wish to make use of them. The CodeIgniter defaults were
| chosen for the least overlap with these conventions, while still
| leaving room for others to be defined in future versions and user
| applications.
| 脚本运行中止状态码
| The three main conventions used for determining exit status codes
| are as follows:
|
| Standard C/C++ Library (stdlibc):
| http://www.gnu.org/software/libc/manual/html_node/Exit-Status.html
| (This link also contains other GNU-specific conventions)
| BSD sysexits.h:
| http://www.gsp.com/cgi-bin/man.cgi?section=3&topic=sysexits
| Bash scripting:
| http://tldp.org/LDP/abs/html/exitcodes.html
|
*/
defined('EXIT_SUCCESS') OR define('EXIT_SUCCESS', 0); // no errors
defined('EXIT_ERROR') OR define('EXIT_ERROR', 1); // generic error
defined('EXIT_CONFIG') OR define('EXIT_CONFIG', 3); // configuration error
defined('EXIT_UNKNOWN_FILE') OR define('EXIT_UNKNOWN_FILE', 4); // file not found
defined('EXIT_UNKNOWN_CLASS') OR define('EXIT_UNKNOWN_CLASS', 5); // unknown class
defined('EXIT_UNKNOWN_METHOD') OR define('EXIT_UNKNOWN_METHOD', 6); // unknown class member
defined('EXIT_USER_INPUT') OR define('EXIT_USER_INPUT', 7); // invalid user input
defined('EXIT_DATABASE') OR define('EXIT_DATABASE', 8); // database error
defined('EXIT__AUTO_MIN') OR define('EXIT__AUTO_MIN', 9); // lowest automatically-assigned error code
defined('EXIT__AUTO_MAX') OR define('EXIT__AUTO_MAX', 125); // highest automatically-assigned error code

你可能感兴趣的:(CI源码)