(PECL eio >= 0.5.0b)
eio_seek — Repositions the offset of the open file associated with the fd argument to the argument offset according to the directive whence
$fd
, int $offset
, int $whence
[, int $pri = EIO_PRI_DEFAULT
[, callable $callback = NULL
[, mixed $data = NULL
]]] )
eio_seek() repositions the offset of the open file associated with
stream, Socket resource, or file descriptor specified by fd to the argument offset according to the directive whence as follows:
EIO_SEEK_SET - Set position equal to offset bytes.EIO_SEEK_CUR - Set position to current location plus offset.EIO_SEEK_END - Set position to end-of-file plus offset.fd
Stream, Socket resource, or numeric file descriptor
offset
Starting point from which data is to be read.
length
Number of bytes to be read.
pri
请求的优先级: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or NULL.
如果是 NULL , pri 将设为
EIO_PRI_DEFAULT.
callback
callback 函数将在请求结束时被调用.
必须符合此原型:
void callback($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_seek() returns request resource on success or FALSE on error.