aio_suspend - Man Page
wait for asynchronous I/O operation or timeout
Library
Real-time library (librt, -lrt)
Synopsis
#include <aio.h> int aio_suspend(const struct aiocb *const aiocb_list[], int nitems, const struct timespec *restrict timeout);
Description
The aio_suspend() function suspends the calling thread until one of the following occurs:
- One or more of the asynchronous I/O requests in the list aiocb_list has completed.
- A signal is delivered.
- timeout is not NULL and the specified time interval has passed. (For details of the timespec structure, see nanosleep(2).)
The nitems argument specifies the number of items in aiocb_list. Each item in the list pointed to by aiocb_list must be either NULL (and then is ignored), or a pointer to a control block on which I/O was initiated using aio_read(3), aio_write(3), or lio_listio(3). (See aio(7) for a description of the aiocb structure.)
If CLOCK_MONOTONIC is supported, this clock is used to measure the timeout interval (see clock_gettime(2)).
Return Value
If this function returns after completion of one of the I/O requests specified in aiocb_list, 0 is returned. Otherwise, -1 is returned, and errno is set to indicate the error.
Errors
- EAGAIN
The call timed out before any of the indicated operations had completed.
- EINTR
The call was ended by signal (possibly the completion signal of one of the operations we were waiting for); see signal(7).
- ENOSYS
aio_suspend() is not implemented.
Attributes
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
---|---|---|
aio_suspend() | Thread safety | MT-Safe |
Standards
POSIX.1-2008.
History
glibc 2.1. POSIX.1-2001.
POSIX doesn't specify the parameters to be restrict; that is specific to glibc.
Notes
One can achieve polling by using a non-NULL timeout that specifies a zero time interval.
If one or more of the asynchronous I/O operations specified in aiocb_list has already completed at the time of the call to aio_suspend(), then the call returns immediately.
To determine which I/O operations have completed after a successful return from aio_suspend(), use aio_error(3) to scan the list of aiocb structures pointed to by aiocb_list.
Bugs
The glibc implementation of aio_suspend() is not async-signal-safe, in violation of the requirements of POSIX.1.
See Also
aio_cancel(3), aio_error(3), aio_fsync(3), aio_read(3), aio_return(3), aio_write(3), lio_listio(3), aio(7), time(7)
Referenced By
aio(7), aio_cancel(3), aio_error(3), aio_fsync(3), aio_read(3), aio_return(3), aio_write(3), lio_listio(3), signal-safety(7).