eio_readahead

(PECL eio >= 0.0.1dev)

eio_readahead — Perform file readahead into page cache

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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.

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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

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callback

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void callback(mixed $data, int $result[, resource $req]);
data

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result

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req

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data

Arbitrary variable passed to callback.

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eio_readahead() returns request resource on success or FALSE on error.