NAME

       aio_suspend - wait for an asynchronous I/O request (REALTIME)

SYNOPSIS

       #include <aio.h>

       int aio_suspend(const struct aiocb * const list[], int nent,
              const struct timespec *timeout);

DESCRIPTION

       The  aio_suspend()  function  shall  suspend  the calling thread until at least one of the
       asynchronous I/O operations referenced by the list argument has completed, until a  signal
       interrupts  the function, or, if timeout is not NULL, until the time interval specified by
       timeout has passed. If any of the aiocb structures in the  list  correspond  to  completed
       asynchronous  I/O  operations (that is, the error status for the operation is not equal to
       [EINPROGRESS]) at the time of the call, the function shall return without  suspending  the
       calling  thread.  The  list  argument  is an array of pointers to asynchronous I/O control
       blocks. The nent argument indicates the number  of  elements  in  the  array.  Each  aiocb
       structure  pointed  to  has  been  used  in  initiating  an  asynchronous  I/O request via
       aio_read(), aio_write(), or lio_listio().  This array may contain NULL pointers, which are
       ignored. If this array contains pointers that refer to aiocb structures that have not been
       used in submitting asynchronous I/O, the effect is undefined.

       If the time interval indicated in the timespec structure  pointed  to  by  timeout  passes
       before  any  of  the  I/O  operations referenced by list are completed, then aio_suspend()
       shall return with an error.    If the Monotonic Clock option is supported, the clock  that
       shall be used to measure this time interval shall be the CLOCK_MONOTONIC clock.

RETURN VALUE

       If  the  aio_suspend() function returns after one or more asynchronous I/O operations have
       completed, the function shall return zero. Otherwise, the function shall return a value of
       -1 and set errno to indicate the error.

       The  application may determine which asynchronous I/O completed by scanning the associated
       error and return status using aio_error() and aio_return(), respectively.

ERRORS

       The aio_suspend() function shall fail if:

       EAGAIN No asynchronous I/O indicated in the list referenced by list completed in the  time
              interval indicated by timeout.

       EINTR  A signal interrupted the aio_suspend() function. Note that, since each asynchronous
              I/O operation may possibly provoke a signal when it completes,  this  error  return
              may  be  caused by the completion of one (or more) of the very I/O operations being
              awaited.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       The aio_suspend() function is part of the Asynchronous Input and Output  option  and  need
       not be available on all implementations.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       aio_read()   ,   aio_write()   ,   lio_listio()   ,   the   Base   Definitions  volume  of
       IEEE Std 1003.1-2001, <aio.h>

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1,  2003  Edition,  Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard,  the  original  IEEE  and  The  Open Group Standard is the referee document. The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .