io_cancel - cancel an outstanding asynchronous I/O operation
#include <linux/aio_abi.h> /* Defines needed types */
int io_cancel(aio_context_t ctx_id, struct iocb *iocb,
struct io_event *result);
: There is no glibc wrapper for this system call; see NOTES.
() system call attempts to cancel an asynchronous I/O
operation previously submitted with io_submit
(2). The iocb
argument describes the operation to be canceled and the ctx_id
is the AIO context to which the operation was submitted. If the operation is
successfully canceled, the event will be copied into the memory pointed to by
without being placed into the completion queue.
On success, io_cancel
() returns 0. For the failure return, see NOTES.
- The iocb specified was not canceled.
- One of the data structures points to invalid data.
- The AIO context specified by ctx_id is invalid.
- io_cancel() is not implemented on this
The asynchronous I/O system calls first appeared in Linux 2.5.
() is Linux-specific and should not be used in programs that are
intended to be portable.
Glibc does not provide a wrapper function for this system call. You could invoke
it using syscall
(2). But instead, you probably want to use the
() wrapper function provided by libaio
Note that the libaio
wrapper function uses a different type
) for the ctx_id
argument. Note also that the
wrapper does not follow the usual C library conventions for
indicating errors: on error it returns a negated error number (the negative of
one of the values listed in ERRORS). If the system call is invoked via
(2), then the return value follows the usual conventions for
indicating an error: -1, with errno
set to a (positive) value that
indicates the error.
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