NAME

       aio.h - asynchronous input and output (REALTIME)

SYNOPSIS

       #include <aio.h>

DESCRIPTION

       The  <aio.h>  header  shall  define  the  aiocb structure which shall include at least the
       following members:

              int             aio_fildes     File descriptor.
              off_t           aio_offset     File offset.
              volatile void  *aio_buf        Location of buffer.
              size_t          aio_nbytes     Length of transfer.
              int             aio_reqprio    Request priority offset.
              struct sigevent aio_sigevent   Signal number and value.
              int             aio_lio_opcode Operation to be performed.

       This header shall also include the following constants:

       AIO_ALLDONE
              A return value indicating that none of the requested operations could  be  canceled
              since they are already complete.

       AIO_CANCELED
              A return value indicating that all requested operations have been canceled.

       AIO_NOTCANCELED

              A  return  value  indicating  that  some  of  the requested operations could not be
              canceled since they are in progress.

       LIO_NOP
              A lio_listio() element operation option indicating that no transfer is requested.

       LIO_NOWAIT
              A lio_listio() synchronization operation indicating that the calling thread  is  to
              continue  execution  while  the  lio_listio()  operation is being performed, and no
              notification is given when the operation is complete.

       LIO_READ
              A lio_listio() element operation option requesting a read.

       LIO_WAIT
              A lio_listio() synchronization operation indicating that the calling thread  is  to
              suspend until the lio_listio() operation is complete.

       LIO_WRITE
              A lio_listio() element operation option requesting a write.

       The  following  shall be declared as functions and may also be defined as macros. Function
       prototypes shall be provided.

              int      aio_cancel(int, struct aiocb *);
              int      aio_error(const struct aiocb *);
              int      aio_fsync(int, struct aiocb *);
              int      aio_read(struct aiocb *);
              ssize_t  aio_return(struct aiocb *);
              int      aio_suspend(const struct aiocb *const[], int,
                           const struct timespec *);
              int      aio_write(struct aiocb *);
              int      lio_listio(int, struct aiocb *restrict const[restrict], int,
                           struct sigevent *restrict);

       Inclusion of the <aio.h> header may make visible symbols defined in the headers <fcntl.h>,
       <signal.h>, <sys/types.h>, and <time.h>.

       The following sections are informative.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       <fcntl.h>  ,  <signal.h>  ,  <sys/types.h>  ,  <time.h>  , the System Interfaces volume of
       IEEE Std 1003.1-2001, fsync(), lseek(), read(), write()

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 .