This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
aio_suspend — wait for an asynchronous I/O request
int aio_suspend(const struct aiocb *const list, int nent,
const struct timespec *timeout);
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
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
The application may determine which asynchronous I/O completed by
scanning the associated error and return status using aio_error() and
The aio_suspend() function shall fail if:
- No asynchronous I/O indicated in the list referenced by list
completed in the time interval indicated by timeout.
- 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.
aio_read(), aio_write(), lio_listio()
The Base Definitions volume of POSIX.1‐2017,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 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 .
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