#include <aio.h> int
Fo lio_listio
Fa int mode
Fa struct aiocb * const list[]
Fa int nent
Fa struct sigevent *sig
Fc
DESCRIPTION
The
lio_listio ();
function initiates a list of I/O requests with a single function call.
The
Fa list
argument is an array of pointers to
Vt aiocb
structures describing each operation to perform,
with
Fa nent
elements.
NULL
elements are ignored.
The
aio_lio_opcode
field of each
Vt aiocb
specifies the operation to be performed.
The following operations are supported:
LIO_READ
Read data as if by a call to
aio_read2.
LIO_NOP
No operation.
LIO_WRITE
Write data as if by a call to
aio_write2.
If the
Fa mode
argument is
LIO_WAIT
lio_listio ();
does not return until all the requested operations have been completed.
If
Fa mode
is
LIO_NOWAIT
the requests are processed asynchronously, and the signal specified by
Fa sig
is sent when all operations have completed.
If
Fa sig
is
NULL
the calling process is not notified of I/O completion.
The order in which the requests are carried out is not specified;
in particular, there is no guarantee that they will be executed in
the order 0, 1, ...,
Fa nent Ns -1 .
RETURN VALUES
If
Fa mode
is
LIO_WAIT
the
lio_listio ();
function returns 0 if the operations completed successfully,
otherwise -1.
If
Fa mode
is
LIO_NOWAIT
the
lio_listio ();
function returns 0 if the operations are successfully queued,
otherwise -1.
ERRORS
The
lio_listio ();
function will fail if:
Bq Er EAGAIN
There are not enough resources to enqueue the requests.
Bq Er EAGAIN
The request would cause the system-wide limit
AIO_MAX
to be exceeded.
Bq Er EINVAL
The
Fa mode
argument is neither
LIO_WAIT
nor
LIO_NOWAIT
or
Fa nent
is greater than
AIO_LISTIO_MAX
Bq Er EINTR
A signal interrupted the system call before it could be completed.
Bq Er EIO
One or more requests failed.
In addition, the
lio_listio ();
function may fail for any of the reasons listed for
aio_read2
and
aio_write2.
If
lio_listio ();
succeeds, or fails with an error code of
Er EAGAIN , EINTR ,
or
Er EIO ,
some of the requests may have been initiated.
The caller should check the error status of each
Vt aiocb
structure individually by calling
aio_error2.