(PECL eio >= 0.0.1dev)
eio_readahead — Perform file readahead into page cache
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.
The file descriptor
Starting point from which data is to be read.
Number of bytes to be read.
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 function is called when the request is done. It should match the following prototype:
void callback($data, $result);
Arbitrary variable passed to callback.
eio_readahead() returns request resource on success or FALSE on error.