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LIO_LISTIO(2)		    BSD	System Calls Manual		 LIO_LISTIO(2)

NAME
     lio_listio	-- list	directed I/O (REALTIME)

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <aio.h>

     int
     lio_listio(int mode, struct aiocb * const list[], int nent,
	 struct	sigevent *sig);

DESCRIPTION
     The lio_listio() function initiates a list	of I/O requests	with a single
     function call.  The list argument is an array of pointers to aiocb	struc-
     tures describing each operation to	perform, with nent elements.  NULL el-
     ements are	ignored.

     The aio_lio_opcode	field of each aiocb specifies the operation to be per-
     formed.  The following operations are supported:

     LIO_READ	Read data as if	by a call to aio_read(2).

     LIO_NOP	No operation.

     LIO_WRITE	Write data as if by a call to aio_write(2).

     If	the mode argument is LIO_WAIT, lio_listio() does not return until all
     the requested operations have been	completed.  If mode is LIO_NOWAIT, sig
     can be used to request asynchronous notification when all operations have
     completed.	 If sig	is NULL, no notification is sent.

     For SIGEV_KEVENT notifications, the posted	kevent will contain:

     Member    Value
     ident     list
     filter    EVFILT_LIO
     udata     value stored in sig-_sigev_value

     For SIGEV_SIGNO and SIGEV_THREAD_ID notifications,	the information	for
     the queued	signal will include SI_ASYNCIO in the si_code field and	the
     value stored in sig-_sigev_value in the si_value field.

     For SIGEV_THREAD notifications, the value stored in sig-_sigev_value is
     passed to the sig-_sigev_notify_function as described in sigevent(3).

     The order in which	the requests are carried out is	not specified; in par-
     ticular, there is no guarantee that they will be executed in the order 0,
     1,	..., nent-1.

RETURN VALUES
     If	mode is	LIO_WAIT, the lio_listio() function returns 0 if the opera-
     tions completed successfully, otherwise -1.

     If	mode is	LIO_NOWAIT, the	lio_listio() function returns 0	if the opera-
     tions are successfully queued, otherwise -1.

ERRORS
     The lio_listio() function will fail if:

     [EAGAIN]		There are not enough resources to enqueue the re-
			quests.

     [EAGAIN]		The request would cause	the system-wide	limit
			{AIO_MAX} to be	exceeded.

     [EINVAL]		The mode argument is neither LIO_WAIT nor LIO_NOWAIT,
			or nent	is greater than	{AIO_LISTIO_MAX}.

     [EINVAL]		The asynchronous notification method in
			sig-_sigev_notify is invalid or	not supported.

     [EINTR]		A signal interrupted the system	call before it could
			be completed.

     [EIO]		One or more requests failed.

     In	addition, the lio_listio() function may	fail for any of	the reasons
     listed for	aio_read(2) and	aio_write(2).

     If	lio_listio() succeeds, or fails	with an	error code of EAGAIN, EINTR,
     or	EIO, some of the requests may have been	initiated.  The	caller should
     check the error status of each aiocb structure individually by calling
     aio_error(2).

SEE ALSO
     aio_error(2), aio_read(2),	aio_write(2), read(2), write(2), sigevent(3),
     siginfo(3), aio(4)

STANDARDS
     The lio_listio() function is expected to conform to IEEE Std 1003.1-2001
     ("POSIX.1").

BSD				 Oct 23, 2017				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS

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