(PECL eio >= 0.0.1dev)
eio_ftruncate — Truncate a file
$fd
[, int $offset = 0
[, int $pri = EIO_PRI_DEFAULT
[, callable $callback = NULL
[, mixed $data = NULL
]]]] )
eio_ftruncate() causes a regular file referenced by
fd file descriptor to be truncated to precisely
length bytes.
fd
The file descriptor.
offset
Offset from beginning of the file
pri
请求的优先级: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or NULL.
如果是 NULL , pri 将设为
EIO_PRI_DEFAULT.
callback
callback 函数将在请求结束时被调用.
必须符合此原型:
void callback($data, $result);
$data 是传给该请求的特定数据.
$result 包含特定请求的结果值, 通常是相应的系统调用的返回值.
data
Arbitrary variable passed to callback.
eio_ftruncate() returns request resource on success or FALSE on error.