(PECL eio >= 0.0.1dev)
eio_ftruncate — Truncate a file
$fd
[, int $offset = 0
[, int $pri = EIO_PRI_DEFAULT
[, callable $callback = NULL
[, mixed $data = NULL
]]]] )
eio_ftruncate() causes a regular file referenced by
fd file descriptor to be truncated to precisely
length bytes.
fd
Stream, Socket resource, or numeric file descriptor.
offset
Offset from beginning of the file
pri
请求的优先级: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or NULL.
如果是 NULL , pri 将设为
EIO_PRI_DEFAULT.
callback
callback 函数将在请求结束时被调用.
必须符合此原型:
void callback($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.