table of contents
| LIO_LISTIO(2) | System Calls Manual | LIO_LISTIO(2) |
NAME¶
lio_listio —
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¶
Thelio_listio() function initiates a list of I/O
requests with a single function call. The list argument
is an array of pointers to aiocb structures describing
each operation to perform, with nent elements.
NULL elements are ignored.
The aio_lio_opcode field of each aiocb specifies the operation to be performed. 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 particular, there is no guarantee that they will be executed in the order 0, 1, ..., nent-1.
RETURN VALUES¶
If mode isLIO_WAIT, the
lio_listio() function returns 0 if the operations
completed successfully, otherwise -1.
If mode is
LIO_NOWAIT, the lio_listio()
function returns 0 if the operations are successfully queued, otherwise
-1.
ERRORS¶
Thelio_listio() function will fail if:
- [
EAGAIN] - There are not enough resources to enqueue the requests.
- [
EAGAIN] - The request would cause the system-wide limit
AIO_MAXto be exceeded. - [
EINVAL] - The mode argument is neither
LIO_WAITnorLIO_NOWAIT, or nent is greater thanAIO_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¶
Thelio_listio() function is expected to conform to
IEEE Std 1003.1-2001 (“POSIX.1”).
| July 15, 2016 | Linux 4.9.0-9-amd64 |