eio_readahead
mixed$fd,
int$offset,
int$length,
[int$pri = EIO_PRI_DEFAULT],
[callable$callback = NULL],
[mixed$data = NULL]
): resource
eio_readahead populates the page cache with data from a file so that subsequent reads from that file will not block on disk I/O. See READAHEAD(2) man page for details.
Parameters
- 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
-
The request priority: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or null. If null passed, pri internally is set to EIO_PRI_DEFAULT.
- callback
-
callback function is called when the request is done. It should match the following prototype:
void callback(mixed $data, int $result[, resource $req]);- data
is custom data passed to the request.
- result
request-specific result value; basically, the value returned by corresponding system call.
- req
is optional request resource which can be used with functions like eio_get_last_error
- data
-
Arbitrary variable passed to callback.
Return Values
eio_readahead returns request resource on success, or false on failure.