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This document uses PHP Chinese website manual Release
(PHP 4, PHP 5, PHP 7)
linkinfo — 获取一个连接的信息
$path
)获取一个连接的信息。
本函数用来验证一个连接(由 path
所指向的)是否确实存在(使用 stat.h 中的 S_ISLNK
宏同样的方法)。
path
连接的路径。
linkinfo() 返回 lstat
系统调用所返回的 UNIX C stat 结构中的 st_dev
字段。 如果出错则返回 0 或 FALSE
。
版本 | 说明 |
---|---|
5.3.0 | Windows 平台上开始可用(Vista、Server 2008 或更高版本)。 |
Example #1 linkinfo() 例子
<?php
echo linkinfo ( '/vmlinuz' ); // 835
?>
[#1] rjb at robertjbrown dot com [2012-02-21 01:14:39]
I expected this function to return FALSE or 0 if a symbolic link did not exist (per the documentation above), but that's not what happened. Reading the man page for the Linux kerne's stat call here: http://www.kernel.org/doc/man-pages/online/pages/man2/stat.2.html it says this:
RETURN VALUE - On success, zero is returned. On error, -1 is returned, and errno is set appropriately.
... which is what is happening in my case. I am doing a linkinfo('/path/to/file'); on a missing symlink, and I get back a value of -1. As we know, a value of -1 is not going to evaluate to a FALSE or 0.
My point - be careful with return values for missing symlinks.