fileatime
(PHP 4, PHP 5)
fileatime — Gets last access time of file
說明
$filename
)Gets the last access time of the given file.
參數
-
filename -
Path to the file.
回傳值
Returns the time the file was last accessed, 或者在失敗時回傳 FALSE.
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));
}
?>
錯誤/例外
失敗時拋出E_WARNING警告。
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:
注意：不同檔案系統對時間的判斷方法可能是不盡相同。
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Supported Protocols and Wrappers 來看哪些 wrapper 支援 stat() 系列函式的功能。
參見
- filemtime() - Gets file modification time
- fileinode() - Gets file inode
- date() - Format a local time/date
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