lio_listio(2)							System Calls Manual						     lio_listio(2)

NAME

       lio_listio() - start a list of asynchronous I/O operations

SYNOPSIS


DESCRIPTION

       The  function  allows  the calling process to request a list of asynchronous I/O operations with a single function call.  The function call
       returns when all operation requests have been enqueued for processing.  At this point, processing of the  operations  may  proceed  concur-
       rently with execution of the calling process or thread.

       The  argument  is an array of pointers to structures.  Each in is treated as if it were being handled in a separate call to or depending on
       the value of its When is the is treated as though it had been referenced in a call to and the and fields are interpreted accordingly.  When
       is the is treated as though it had been referenced in a call to and the and fields are interpreted accordingly.	If is nothing is enqueued.

       If  an  error condition is detected that prevents the list from being processed, returns and sets to indicate the cause of the failure.	If
       any requests are enqueued by the call to and is then the function returns only after all enqueued operation requests have  completed.   The
       sig argument of the call is ignored.  If is the function returns as soon as all requests are enqueued.  The action specified by sig is per-
       formed after all enqueued requests have completed.

       Once the requested operations have been successfully enqueued, an and function referencing the corresponding from must be used to determine
       their  status  and  any	error  conditions,  including  those normally reported by or as appropriate.  Requests remain enqueued and consume
       process and system resources until is called for each one.

       Re-using or deallocating memory referred to by the or any referenced in the while an asynchronous I/O operation is outstanding (i.e. before
       has been called) may produce unpredictable results.

       To use this function, link in the realtime library by specifying on the compiler or linker command line.

RETURN VALUE

       When is set, returns the following values:

	      Success.	     All of the non-empty operations, if any, were successfully enqueued.

	      Failure or partial success.
			     At  least	one  requested	operation  was	either	not  enqueued  or completed with an error before the function call
			     returned.	is set to indicate the error.

       When is set, returns the following values:

	      Success.	     All of the non-empty operations, if any, were successfully enqueued and completed.

	      Failure or partial success.
			     At least one requested operation was either not enqueued or completed with an error.  is set to indicate the error.

       The three values and are the only ones associated with partial success.	and must be used to determine the outcomes of individual requests.

ERRORS

       If detects one of the following error conditions, is set to the indicated value:

	      [EAGAIN]	     At least one request could not be queued either because of a resource shortage or because the per-process or  system-
			     wide limit on asynchronous I/O operations or asynchronous threads would have been exceeded.

	      [EINVAL]	     The specified by sig is not valid.

	      [EINVAL]	     The argument is neither nor

	      [EINVAL]	     The  value  of  the  argument is negative or greater than the maximum value allowed. The maximum value allowed can be
			     obtained using the call with the argument

	      [EINTR]	     The argument was and a signal was delivered while waiting for the requested operations to complete.  This signal  may
			     result  from  completion  of  one or more of the requested operations and other requests may still be pending or com-
			     pleted.

       Once an operation has been enqueued by the following errors, in addition to all of the errors normally reported by the appropriate or func-
       tion, may be reported asynchronously by a subsequent call to or referencing its

	      [EBADF]	     The was not a valid file descriptor open for reading or writing as appropriate to the

	      [EINVAL]	     The value of is not valid, or the value of is invalid, or the file offset implied by or is not valid.

	      [EIO]	     One or more of the enqueued operations did not complete successfully.

EXAMPLE

       The  following  code  sequence  and  call to starts two asynchronous write operations and one asynchronous read operation and waits for all
       operations to complete.

SEE ALSO

       aio_cancel(2), aio_error(2), aio_fsync(2), aio_read(2), aio_return(2), aio_suspend(2), aio_write(2), read(2), write(2), aio(5).

STANDARDS CONFORMANCE

																     lio_listio(2)