php man page for eio_dup2

EIO_DUP2(3)								 1							       EIO_DUP2(3)

eio_dup2 - Duplicate a file descriptor

SYNOPSIS
       resource eio_dup2 (mixed  $fd, mixed  $fd2, [int  $pri = EIO_PRI_DEFAULT], [callable  $callback = NULL], [mixed	$data = NULL])

DESCRIPTION
       eio_dup2(3) duplicates file descriptor.

PARAMETERS
	      o $fd
		- Source stream, Socket resource, or numeric file descriptor

	      o $fd2
		- Target stream, Socket resource, or numeric file descriptor

	      o $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.

	      o $callback
		-$callback function is called when the request is done. It should match the following prototype:

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

		     o $data
		       -is custom data passed to the request.

		     o $result
		       -request-specific result value; basically, the value returned by corresponding system call.

		     o $req
		       -is optional request resource which can be used with functions like eio_get_last_error(3)

	      o $data
		- Arbitrary variable passed to $callback.

RETURN VALUES
       eio_dup2(3) returns request resource on success or FALSE on error.

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