PHP - Manual: eio_seek
2024-11-15
(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
$fd
,$offset
,$whence
,$pri
= EIO_PRI_DEFAULT,$callback
= NULL,$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
或 null
。如果是
null
,pri
将设为
EIO_PRI_DEFAULT
。
callback
callback
函数在请求完成时被调用。其应匹配一下原型:
void callback(mixed $data, int $result[, resource $req]);
data
传递给请求的用户数据。
result
针对请求的结果的值。通常是相应的系统调用返回的值。
req
可选的请求资源,可被 eio_get_last_error() 之类的函数使用。
data
Arbitrary variable passed to callback
.
eio_seek() returns request resource on success, 或者在失败时返回 false
.