fileatime
(PHP 4, PHP 5)
fileatime — Gets last access time of file
說明
Gets the last access time of the given file.
參數
- filename
-
Path to the file.
Return值
Returns the time the file was last accessed, or FALSE in case of an error. The time is returned as a Unix timestamp.
範例
Example#1 fileatime() example
<?php
// outputs e.g. somefile.txt was last accessed: December 29 2002 22:16:23.
$filename = 'somefile.txt';
if (file_exists($filename)) {
echo "$filename was last accessed: " . date("F d Y H:i:s.", fileatime($filename));
}
?>
註釋
Note: The atime of a file is supposed to change whenever the data blocks of a file are being read. This can be costly performance-wise when an application regularly accesses a very large number of files or directories.
Some Unix filesystems can be mounted with atime updates disabled to increase the performance of such applications; USENET news spools are a common example. On such filesystems this function will be useless.
Note: 本函式的結果會被存入緩衝區。詳情參見 clearstatcache()。
自 PHP 5.0.0 起本函式也可被某些 URL wrapper 使用。參考List of Supported Protocols/Wrappers 來看哪些 wrapper 支援 stat() 系列函式的功能。