.\" Copyright (C) 2025 Jens Axboe <axboe@kernel.dk>
.\"
.\" SPDX-License-Identifier: LGPL-2.0-or-later
.\"
.TH io_uring_cq_eventfd_toggle 3 "January 18, 2025" "liburing-2.4" "liburing Manual"
.SH NAME
io_uring_cq_eventfd_toggle \- toggle eventfd notifications on or off
.SH SYNOPSIS
.nf
.B #include <liburing.h>
.PP
.BI "int io_uring_cq_eventfd_toggle(struct io_uring *" ring ", bool " enabled ");"
.fi
.SH DESCRIPTION
.PP
The
.BR io_uring_cq_eventfd_toggle (3)
function toggles eventfd notifications for the io_uring instance specified by
.IR ring .
If
.I enabled
is
.BR true ,
eventfd notifications are enabled. If
.I enabled
is
.BR false ,
they are disabled.

An eventfd must first be registered with the ring using
.BR io_uring_register_eventfd (3)
or
.BR io_uring_register_eventfd_async (3)
before this function can be used.

This can be useful when the application wants to temporarily stop receiving
eventfd notifications, for example during a batch processing phase.

.SH RETURN VALUE
Returns 0 on success. On error, a negative errno value is returned:
.TP
.B -EOPNOTSUPP
The kernel does not support toggling eventfd notifications, or no eventfd
is registered.
.SH SEE ALSO
.BR io_uring_register_eventfd (3),
.BR io_uring_register_eventfd_async (3),
.BR io_uring_cq_eventfd_enabled (3)