io_cancel(2) — Linux manual page
io_cancel(2) System Calls Manual io_cancel(2)
NAME
io_cancel - cancel an outstanding asynchronous I/O operation
LIBRARY
Standard C library (libc, -lc) Alternatively, Asynchronous I/O library (libaio, -laio); see VERSIONS.
SYNOPSIS
#include <linux/aio_abi.h> /* Definition of needed types */ #include <sys/syscall.h> /* Definition of SYS_* constants */ #include <unistd.h> int syscall(SYS_io_cancel, aio_context_t ctx_id, struct iocb *iocb, struct io_event *result);
DESCRIPTION
Note: this page describes the raw Linux system call interface. The wrapper function provided by libaio uses a different type for the ctx_id argument. See VERSIONS. The io_cancel() 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 argument 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 result without being placed into the completion queue.
RETURN VALUE
On success, io_cancel() returns 0. For the failure return, see VERSIONS.
ERRORS
EAGAIN The iocb specified was not canceled. EFAULT One of the data structures points to invalid data. EINVAL The AIO context specified by ctx_id is invalid. ENOSYS io_cancel() is not implemented on this architecture.
VERSIONS
You probably want to use the io_cancel() wrapper function provided by libaio. Note that the libaio wrapper function uses a different type (io_context_t) for the ctx_id argument. Note also that the libaio 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 syscall(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.
STANDARDS
Linux.
HISTORY
Linux 2.5.
SEE ALSO
io_destroy(2), io_getevents(2), io_setup(2), io_submit(2), aio(7)
COLOPHON
This page is part of the man-pages (Linux kernel and C library user-space interface documentation) project. Information about the project can be found at ⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report for this manual page, see ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩. This page was obtained from the tarball man-pages-6.9.1.tar.gz fetched from ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on 2024-06-26. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up- to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to man-pages@man7.org Linux man-pages 6.9.1 2024-05-02 io_cancel(2)
Pages that refer to this page: io_destroy(2), io_getevents(2), io_setup(2), io_submit(2), syscalls(2), aio(7)