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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | VERSIONS | ATTRIBUTES | CONFORMING TO | NOTES | SEE ALSO | COLOPHON |
LIO_LISTIO(3) Linux Programmer's Manual LIO_LISTIO(3)
lio_listio - initiate a list of I/O requests
#include <aio.h>
int lio_listio(int mode, struct aiocb *const aiocb_list[],
int nitems, struct sigevent *sevp);
Link with -lrt.
The lio_listio() function initiates the list of I/O operations
described by the array aiocb_list.
The mode operation has one of the following values:
LIO_WAIT The call blocks until all operations are complete. The
sevp argument is ignored.
LIO_NOWAIT The I/O operations are queued for processing and the call
returns immediately. When all of the I/O operations
complete, asynchronous notification occurs, as specified
by the sevp argument; see sigevent(7) for details. If
sevp is NULL, no asynchronous notification occurs.
The aiocb_list argument is an array of pointers to aiocb structures
that describe I/O operations. These operations are executed in an
unspecified order. The nitems argument specifies the size of the
array aiocb_list. null pointers in aiocb_list are ignored.
In each control block in aiocb_list, the aio_lio_opcode field
specifies the I/O operation to be initiated, as follows:
LIO_READ Initiate a read operation. The operation is queued as for
a call to aio_read(3) specifying this control block.
LIO_WRITE Initiate a write operation. The operation is queued as for
a call to aio_write(3) specifying this control block.
LIO_NOP Ignore this control block.
The remaining fields in each control block have the same meanings as
for aio_read(3) and aio_write(3). The aio_sigevent fields of each
control block can be used to specify notifications for the individual
I/O operations (see sigevent(7)).
If mode is LIO_NOWAIT, lio_listio() returns 0 if all I/O operations
are successfully queued. Otherwise, -1 is returned, and errno is set
to indicate the error.
If mode is LIO_WAIT, lio_listio() returns 0 when all of the I/O
operations have completed successfully. Otherwise, -1 is returned,
and errno is set to indicate the error.
The return status from lio_listio() provides information only about
the call itself, not about the individual I/O operations. One or
more of the I/O operations may fail, but this does not prevent other
operations completing. The status of individual I/O operations in
aiocb_list can be determined using aio_error(3). When an operation
has completed, its return status can be obtained using aio_return(3).
Individual I/O operations can fail for the reasons described in
aio_read(3) and aio_write(3).
The lio_listio() function may fail for the following reasons:
EAGAIN Out of resources.
EAGAIN The number of I/O operations specified by nitems would cause
the limit AIO_MAX to be exceeded.
EINTR mode was LIO_WAIT and a signal was caught before all I/O
operations completed; see signal(7). (This may even be one of
the signals used for asynchronous I/O completion
notification.)
EINVAL mode is invalid, or nitems exceeds the limit AIO_LISTIO_MAX.
EIO One of more of the operations specified by aiocb_list failed.
The application can check the status of each operation using
aio_return(3).
If lio_listio() fails with the error EAGAIN, EINTR, or EIO, then some
of the operations in aiocb_list may have been initiated. If
lio_listio() fails for any other reason, then none of the I/O
operations has been initiated.
The lio_listio() function is available since glibc 2.1.
For an explanation of the terms used in this section, see
attributes(7).
┌─────────────┬───────────────┬─────────┐
│Interface │ Attribute │ Value │
├─────────────┼───────────────┼─────────┤
│lio_listio() │ Thread safety │ MT-Safe │
└─────────────┴───────────────┴─────────┘
POSIX.1-2001, POSIX.1-2008.
It is a good idea to zero out the control blocks before use. The
control blocks must not be changed while the I/O operations are in
progress. The buffer areas being read into or written from must not
be accessed during the operations or undefined results may occur.
The memory areas involved must remain valid.
Simultaneous I/O operations specifying the same aiocb structure
produce undefined results.
aio_cancel(3), aio_error(3), aio_fsync(3), aio_return(3),
aio_suspend(3), aio_write(3), aio(7)
This page is part of release 4.12 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
2016-10-08 LIO_LISTIO(3)
Pages that refer to this page: aio_cancel(3), aio_error(3), aio_fsync(3), aio_read(3), aio_return(3), aio_suspend(3), aio_write(3), getaddrinfo_a(3), aio(7), sigevent(7)