php5 通用兼容的公共文件.

<?php
# 基础抬头 其中第三项释放的信息在浏览器debug时可见.
header('Content-language: zh'); 
header('Content-type: text/html; charset=utf-8');
header('X-Powered-By: PHP/-'.phpversion());
# 设置php文件永远不缓存. 可以在后面进行叠加影响的.
header('Pragma: no-cache');
header('Cache-Control: private',false); // required for certain browsers 
header('Cache-Control: no-cache, no-store, max-age=0, must-revalidate'); 
header('Expires: '.gmdate('D, d M Y H:i:s') . ' GMT');
header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . ' GMT');
# 设置一个结束时调用的函数. 请自行修改函数名.
function_exists('register_shutdown_function') && register_shutdown_function('ini_end');
# 设置执行时间,内部字符编码.
set_time_limit($set_time = 3600);
mb_internal_encoding('utf-8');
# 核心设置
ini_sets('session.name','PHPSESSID');
ini_sets('max_execution_time',$set_time);
ini_sets('max_input_time',$set_time);
ini_sets('zend.ze1_compatibility_mode', false);
ini_sets('precision', 72);
ini_sets('session.gc_maxlifetime',3600); //设置垃圾回收最大生存时间
ini_sets('session.gc_probability',30); //和session.gc_divisor一起构成清除垃圾的执行几率
ini_sets('session.gc_divisor',100);
ini_sets('date.timezone','UTC');
ini_sets('display_errors', 'Off');
error_reporting(E_ALL & ~E_NOTICE);
ini_http_server(); // this href
# 当$_SESSION数组为空时, 才初始化session.
if (!isset($_SESSION)) {
session_start();
}
# 当gzip没有自动启动时, 才启动gzip压缩.
if (!ini_get('zlib.output_compression')){
!ob_start('ob_gzhandler')?ob_start():ob_start('ob_gzhandler');
}
# 判断对引入字符的转入判断. 都设置为假.
if (version_compare(PHP_VERSION, '5.3.0', '<') && function_exists('set_magic_quotes_runtime')) {
set_magic_quotes_runtime(false);
}
# 对get post, cookie数组进行反转义工作, 以便让其与php5.3+兼容. 得到的数据都是没有转义的.
if(( function_exists('get_magic_quotes_gpc') && get_magic_quotes_gpc())
 || ( ini_get('magic_quotes_sybase') && ( strtolower(ini_get('magic_quotes_sybase')) != 'off'))){
 foreach($_GET as $k => $v) $_GET[$k] = stripslashes($v);
 foreach($_POST as $k => $v) $_POST[$k] = stripslashes($v);
 foreach($_COOKIE as $k => $v) $_COOKIE[$k] = stripslashes($v);
}
# 清空$_ENV数组, 释放掉$_SERVER数组中几个关键性数值. 
unset($_ENV, $_SERVER['MIBDIRS'],$_SERVER['MYSQL_HOME'],$_SERVER['OPENSSL_CONF'],$_SERVER['PHP_PEAR_SYSCONF_DIR'],$_SERVER['PHPRC'],$_SERVER['SystemRoot'],$_SERVER['COMSPEC'],$_SERVER['PATHEXT'], $_SERVER['WINDIR'],$_SERVER['PATH']);
# 一些函数.
function ini_end(){}
function ini_sets($key, $val){return @ini_set($key, $val);}
function ini_http_server(){
 if (!$_SERVER['REQUEST_URI']) { // IIS 5 compatibility
 $_SERVER['REQUEST_URI'] = $_SERVER['ORIG_PATH_INFO'];
}
 if (!strpos($_SERVER['REQUEST_URI'], '?') && $_SERVER['QUERY_STRING'] != '') { // IIS 7 compatibility
 $_SERVER['REQUEST_URI'] .= '?'.$_SERVER['QUERY_STRING'];
}
 $_SERVER['REQUEST_URI'] = strtr($_SERVER['REQUEST_URI'], array('&&'=>'&'));
 $HTTPS = $_SERVER['HTTPS'] && strcasecmp($_SERVER['HTTPS'], 'off');
 $php_selfs = rawurlencode(dirname($_SERVER['SCRIPT_NAME']));
 $php_selfs = strtr($php_selfs, array('%2F'=>'/','%5C'=>'/'));
 $php_selfs = trim($php_selfs, '/');
if($php_selfs)
 $_SERVER['REQUEST_URI'] = strtr($_SERVER['REQUEST_URI'], array($php_selfs.'/'=>''));
 $httppre = (!$HTTPS)?'http':'https';
 if($_SERVER['SERVER_PORT'] !== '80' && $_SERVER['SERVER_PORT'] !== '443'){
 $host = trim($httppre.'://'.$_SERVER['HTTP_HOST'].':'.$_SERVER['SERVER_PORT'].'/'.$php_selfs,'/').'/';
}else{
 $php_selfs && $php_selfs ='/'.$php_selfs;
 $host = trim($httppre.'://'.$_SERVER['HTTP_HOST'].$php_selfs,'/').'/';
}
 $files = trim($_SERVER['REQUEST_URI'], './');
 $_SERVER['HTTP_URL'] = $host.$files;
 $_SERVER['HTTP_PATH'] = $_SERVER['DOCUMENT_ROOT'].'/';
 $_SERVER['HTTP_IP'] = max(getenv('SERVER_ADDR'),getenv('REMOTE_ADDR'),getenv('HTTP_X_FORWARDED_FOR'),getenv('HTTP_CLIENT_IP'));
 $_SERVER['HTTP_TIME_FLOAT'] = microtime(true);
 $_SERVER['HTTP_MEMORY_PEAK_USAGE'] = memory_get_peak_usage();
 $_SERVER['HTTP_MEMORY_USAGE'] = memory_get_usage();
 $_SERVER['HTTP_GET'] = $_GET;
 $_SERVER['HTTP_POST'] = $_POST;
 $_SERVER['HTTP_COOKIE'] = $_COOKIE;
}