IO_GETEVENTS(2)                                     Linux Programmer's Manual                                    IO_GETEVENTS(2)



NAME
       io_getevents - read asynchronous I/O events from the completion queue

SYNOPSIS
       #include <linux/time.h>
       #include <libaio.h>

       int io_getevents(aio_context_t ctx_id, long min_nr, long nr,
                        struct io_event *events, struct timespec *timeout);

       Link with -laio.

DESCRIPTION
       io_getevents()  attempts  to read at least min_nr events and up to nr events from the completion queue of the AIO context
       specified by ctx_id.  timeout specifies the amount of time to wait for events, where a NULL timeout waits until at  least
       min_nr events have been seen.  Note that timeout is relative and will be updated if not NULL and the operation blocks.

RETURN VALUE
       On  success,  io_getevents()  returns the number of events read: 0 if no events are available, or less than min_nr if the
       timeout has elapsed.  For the failure return, see NOTES.

ERRORS
       EFAULT Either events or timeout is an invalid pointer.

       EINVAL ctx_id is invalid.  min_nr is out of range or nr is out of range.

       EINTR  Interrupted by a signal handler; see signal(7).

       ENOSYS io_getevents() is not implemented on this architecture.

VERSIONS
       The asynchronous I/O system calls first appeared in Linux 2.5, August 2002.

CONFORMING TO
       io_getevents() is Linux-specific and should not be used in programs that are intended to be portable.

NOTES
       Glibc does not provide a wrapper function for this system call.

       The wrapper provided in libaio for io_getevents() does not follow the usual C library conventions for  indicating  error:
       on  error  it returns a negated error number (the negative of one of the values listed in ERRORS).  If the system call is
       invoked via syscall(2), then the return value follows the usual conventions for indicating an error: -1, with  errno  set
       to a (positive) value that indicates the error.

SEE ALSO
       io_cancel(2), io_destroy(2), io_setup(2), io_submit(2), time(7)

COLOPHON
       This  page  is  part of release 3.25 of the Linux man-pages project.  A description of the project, and information about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



Linux                                                      2008-07-04                                            IO_GETEVENTS(2)