aio.h - asynchronous input and output
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.
The <aio.h> header shall define the off_t, pthread_attr_t, size_t, and ssize_t types as described in <sys/types.h>.
The <aio.h> header shall define the struct timespec structure as described in <time.h>.
The tag sigevent shall be declared as naming an incomplete structure type, the contents of which are described in the <signal.h> header.
The <aio.h> header shall define the following symbolic constants:
- A return value indicating that none of the requested operations could be canceled since they are already complete.
- A return value indicating that all requested operations have been canceled.
A return value indicating that some of the requested operations could not be canceled since they are in progress.
- A lio_listio() element operation option indicating that no transfer is requested.
- 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.
- A lio_listio() element operation option requesting a read.
- A lio_listio() synchronization operation indicating that the calling thread is to suspend until the lio_listio() operation is complete.
- 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>, and <time.h>.
<fcntl.h> , <signal.h> , <sys/types.h> , <time.h>
XSH aio_cancel , aio_error , aio_fsync , aio_read , aio_return , aio_suspend , aio_write , fsync , lio_listio , lseek , read , write
First released in Issue 5. Included for alignment with the POSIX Realtime Extension.
The <aio.h> header is marked as part of the Asynchronous Input and Output option.
The description of the constants is expanded.
The restrict keyword is added to the prototype for lio_listio().
The <aio.h> header is moved from the Asynchronous Input and Output option to the Base.
This reference page is clarified with respect to macros and symbolic constants, and type and structure declarations are added.
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