16hot 的博客

466页，安装xdebug。原文“就像APD一样，你可以运行pear install xdebug 从PECL安装Xdebug。”

这里的pear有误，应当是pecl。

正确方法： pecl install xdebug。

Controlling how web pages are cached is basically done using 2 kind of headers: Expires and Cache-Control

Using the Expire header is really simple. It tells when the page the browser or the proxy downloaded should be fetched again from the web server. In order to use it in your CGI or PHP page, just after the Content-type, you can add the the expire header as shown below:

// calc an offset of 24 hours
  $offset = 3600 * 24;	
// calc the string in GMT not localtime and add the offset
  $expire = "Expires: " . gmdate("D, d M Y H:i:s", time() + $offset) . " GMT";
//output the HTTP header
  Header($expire);

The Cache-Control HTTP Headers is part of the HTTP 1.1 standard. Here you are an example:

  Cache-Control: max-age=3600, must-revalidate

It has a certain number of parameters that can be used:

• max-age=seconds - the number of seconds from the time of the request you wish this objcet to be keep into the cache;
• s-maxage=seconds - like max-age but it only applies to proxy;
• public - tell to handle the content has cacheable even if it would normally be uncacheable, it is used for example for authenticated pages;
• no-cache - force both proxy and browser to validate the document before to provide a cached copy;
• must-revalidate - tell the browser to obey to any information you give them about a webpage;
• proxy-revalidate - like must-revalidate but applies to proxy;

More Headers

But that's not all, you have to consider other 2 headers: Content-Length and Last-Modified.

The Last-Modified is the easier, you just have to output a date in GMT for example:

        $gmt_mtime = gmdate('D, d M Y H:i:s', time() ) . ' GMT';
        header("Last-Modified: " . $gmt_mtime );

Content-Lenght is the harder because you don't know how long is a php page before processing it. If you output a file, for example and image or a PDF, it is simple because before of starting the output you can read the filesize. With dynamic page you have to use the special OB library, see the example:

	ob_start();
	... your php code ...
	... your php code ...
	... your php code ...
	header('Content-Length: ' . ob_get_length());
        ob_end_flush();

The advantage is that you can use:

	ob_start('ob_gzhandler');

Usefull Links

Finally if you want to check the cacheability of your pages there are some urls available:

• Cacheability Engine Query
• the CacheNow! campaign

原文地址：

http://bbs.chinaunix.net/viewthread.php?tid=661015&extra=page%3D1%26amp%3Bfilter%3Ddigest&page=1 

[学习] PHP中的(伪)多线程与多进程

    已经因为没怎么需要，所以没有查这个的资料。最近有一个项目却是需要这样子的功能。

    查看了PHP的手册和他人的例子，了解到基本的两种方法：

(伪)多线程：借助外力
    利用WEB服务器本身的多线程来处理，从WEB服务器多次调用我们需要实现多线程的程序。
    以下转载自：http://www.laikan8.com/21/118472.html

升级到PHP 5.2.2后，出现session_start写入权限问题。

提示信息如下：

Warning: session_start() [function.session-start]: SAFE MODE Restriction in effect. The script whose uid is 2023 is not allowed to access /var/tmp/ owned by uid 0 in /configs/config.inc.php on line 9

Fatal error: session_start() [<a href='function.session-start'>function.session-start</a>]: Failed to initialize storage module: files (path: ) in /configs/config.inc.php on line 9

 后来在php5的changelog里找到一个bug报告。里面提到一个安全模式的bug。默认session的save_path是/var/tmp，这样会要校验权限。在php.ini文件里，显式指定session的save_path为/tmp，重启web服务就解决了。

今天摆弄起dia来，用它画UML。但是光画成UML，不能导出生成代码，仍然是个痛苦的事情。

为此想用umbrello来着，可是我用的 桌面环境，不支持KDE，无法安装umbrello。只好作罢。

找到uml2php，能够将dia生成PHP代码。遗憾的是只有LINUX版本。 后来找到了dia2code这个好东西。他支持导出多种代码。

 # dia2code
dia2code version 0.8.2, Copyright (C) 2000-2001 Javier O'Hara
Dia2Code comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; read the COPYING file for details.

Usage: dia2code [-h|--help] [-d <dir>] [-nc] [-cl <classlist>]
       [-t (ada|c|cpp|idl|java|php|php5|python|shp|sql|csharp)] [-v]
       [-l <license file>] [-ini <initialization file>]<diagramfile>

 # dia2code -t php test.dia

有很多Apache的虚拟主机，若要我一个一个的转换成为Lighttpd的虚拟主机，那太痛苦了。

于是用PHP写成这个小程序。