virtual() is an Apache-specific function which
is similar to
<!--#include virtual...--> in mod_include.
It performs an Apache sub-request. It is useful for including
CGI scripts or .shtml files, or anything else that you would
parse through Apache. Note that for a CGI script, the script
must generate valid CGI headers. At the minimum that means it
must generate a Content-type header.
To run the sub-request, all buffers are terminated and flushed to the browser, pending headers are sent too.
此函数仅在 PHP 作为 Apache 模块安装时才可使用。
The query string can be passed to the included file but
$_GET is copied from the parent script and only
$_SERVER['QUERY_STRING'] is filled with the passed
query string. The query string may only be passed when using Apache 2.
The requested file will not be listed in the Apache access log.
Environment variables set in the requested file are not visible to the calling script.
自 PHP 4.3.3 起也可以在 Netscape/iPlanet/SunONE 服务器的 NSAPI server module 中使用本函数。