eio_readahead
(PECL eio >= 0.0.1dev)
eio_readahead — Perform file readahead into page cache
Description
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, ornull. Ifnullpassed,priinternally is set toEIO_PRI_DEFAULT. -
callback -
callbackfunction 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 error.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.eio-readahead.php