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aiocb

Asynchronous I/O control block

Synopsis:

#include <aio.h>

struct aiocb {
  int             aio_fildes
  off_t           aio_offset
  volatile void  *aio_buf
  size_t          aio_nbytes
  int             aio_reqprio
  struct sigevent aio_sigevent
  int             aio_lio_opcode
}

Description:

aio_fildes

The file descriptor to use in an asynchronous I/O operation.

---

The aio_* functions work with Transparent Distributed Processing; the file descriptor can be one that you've opened across Qnet.

---

aio_offset

The file offset.

aio_buf

A pointer to a buffer.

aio_nbytes

The length of a transfer.

aio_reqprio

The request priority offset.

aio_sigevent

A pointer to a sigevent structure that specifies the signal number and value.

aio_lio_opcode

The operation to be performed; one of the following:

• 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.

Classification:

POSIX 1003.1 AIO

Caveats:

The first time you call an aio_* function, a thread pool is created, making your process multithreaded if it isn't already. The thread pool isn't destroyed until your process ends.

See also:

aio_cancel(), aio_error(), aio_fsync(), aio_read(), aio_return(), aio_suspend(), aio_write(), lio_listio()