lio_listio(3) — Linux manual page


LIO_LISTIO(3)           Linux Programmer's Manual          LIO_LISTIO(3)

NAME         top

       lio_listio - initiate a list of I/O requests

SYNOPSIS         top

       #include <aio.h>

       int lio_listio(int mode, struct aiocb *restrict const aiocb_list[restrict],
                      int nitems, struct sigevent *restrict sevp);

       Link with -lrt.

DESCRIPTION         top

       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:

              The call blocks until all operations are complete.  The
              sevp argument is ignored.

              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:

              Initiate a read operation.  The operation is queued as for
              a call to aio_read(3) specifying this control block.

              Initiate a write operation.  The operation is queued as
              for a call to aio_write(3) specifying this control block.

              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)).

RETURN VALUE         top

       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

ERRORS         top

       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

       EINVAL mode is invalid, or nitems exceeds the limit

       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.

VERSIONS         top

       The lio_listio() function is available since glibc 2.1.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see

       │Interface                             Attribute     Value   │
       │lio_listio()                          │ Thread safety │ MT-Safe │

CONFORMING TO         top

       POSIX.1-2001, POSIX.1-2008.

NOTES         top

       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.

SEE ALSO         top

       aio_cancel(3), aio_error(3), aio_fsync(3), aio_return(3),
       aio_suspend(3), aio_write(3), aio(7)

COLOPHON         top

       This page is part of release 5.13 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

                               2021-03-22                  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)system_data_types(7)