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GNU/Linux man pages

Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

ISBN : 978-2-7460-9712-4
EAN : 9782746097124
(Editions ENI)

GNU/Linux

Debian 7.3.0

(Wheezy)

io_setup(2)


IO_SETUP

IO_SETUP

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
VERSIONS
CONFORMING TO
NOTES
SEE ALSO
COLOPHON

NAME

io_setup − create an asynchronous I/O context

SYNOPSIS

#include <linux/aio_abi.h> /* Defines needed types */

int io_setup(unsigned nr_events, aio_context_t *ctx_idp);

Note: There is no glibc wrapper for this system call; see NOTES.

DESCRIPTION

The io_setup() system call creates an asynchronous I/O context capable of receiving at least nr_events. The ctx_idp argument must not point to an AIO context that already exists, and must be initialized to 0 prior to the call. On successful creation of the AIO context, *ctx_idp is filled in with the resulting handle.

RETURN VALUE

On success, io_setup() returns 0. For the failure return, see NOTES.

ERRORS

EAGAIN

The specified nr_events exceeds the user’s limit of available events.

EFAULT

An invalid pointer is passed for ctx_idp.

EINVAL

ctx_idp is not initialized, or the specified nr_events exceeds internal limits. nr_events should be greater than 0.

ENOMEM

Insufficient kernel resources are available.

ENOSYS

io_setup() is not implemented on this architecture.

VERSIONS

The asynchronous I/O system calls first appeared in Linux 2.5.

CONFORMING TO

io_setup() is Linux-specific and should not be used in programs that are intended to be portable.

NOTES

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 io_setup() wrapper function provided by libaio.

Note that the libaio wrapper function uses a different type (io_context_t *) for the ctx_idp 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.

SEE ALSO

io_cancel(2), io_destroy(2), io_getevents(2), io_submit(2), aio(7)

COLOPHON

This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



io_setup(2)