ftruncate
(PHP 4, PHP 5, PHP 7)
ftruncate — 将文件截断到给定的长度
说明
ftruncate
( resource
$handle
, int $size
) : bool
接受文件指针 handle
作为参数,并将文件大小截取为
size
。
参数
-
handle
-
文件指针。
Note:
The
handle
must be open for writing.
size
The size to truncate to.
Note:
If
size
is larger than the file then the file is extended with null bytes.If
size
is smaller than the file then the file is truncated to that size.
返回值
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
范例
Example #1 File truncation example
<?php
$filename = 'lorem_ipsum.txt';
$handle = fopen($filename, 'r+');
ftruncate($handle, rand(1, filesize($filename)));
rewind($handle);
echo fread($handle, filesize($filename));
fclose($handle);
?>
注释
Note:
The file pointer is not changed.