linkinfo

(PHP 4, PHP 5)

linkinfo — 获取一个连接的信息

说明

int linkinfo ( string $path )

linkinfo() 返回 lstat 系统调用所返回的 UNIX C stat 结构中的 st_dev 字段。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）。如果出错则返回 0 或 FALSE。

Example #1 linkinfo() 例子


<?php

echo linkinfo('/vmlinuz'); // 835

?>

参见 symlink()，link() 和 readlink()。

参数

path: Path to the link.

返回值

linkinfo() returns the st_dev field of the Unix C stat structure returned by the lstat system call. Returns 0 or FALSE in case of error.

更新日志

版本	说明
5.3.0	This function is now available on Windows platforms (Vista, Server 2008 or greater).

范例

Example #2 linkinfo() example


<?php

echo linkinfo('/vmlinuz'); // 835

?>

参见

symlink() - 建立符号连接
link() - 建立一个硬连接
readlink() - 返回符号连接指向的目标

PHP手册 - N: 获取一个连接的信息

用户评论:

rjb at robertjbrown dot com (21-Feb-2012 09:14)

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.