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// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library zx;
@transport("Syscall")
protocol Event {
/// ## Summary
///
/// Create an event.
///
/// ## Declaration
///
/// ```c
/// #include <zircon/syscalls.h>
///
/// zx_status_t zx_event_create(uint32_t options, zx_handle_t* out);
/// ```
///
/// ## Description
///
/// `zx_event_create()` creates an event, which is an object that is signalable. That
/// is, its **ZX_USER_SIGNAL_n** (where *n* is 0 through 7) signals can be
/// manipulated using [`zx_object_signal()`].
///
/// The newly-created handle will have the [basic
/// rights](/docs/concepts/kernel/rights.md#zx_rights_basic) plus **ZX_RIGHT_SIGNAL**.
///
/// ## Rights
///
/// Caller job policy must allow **ZX_POL_NEW_EVENT**.
///
/// ## Return value
///
/// `zx_event_create()` returns **ZX_OK** and a valid event handle (via *out*) on success.
/// On failure, an error value is returned.
///
/// ## Errors
///
/// **ZX_ERR_INVALID_ARGS** *out* is an invalid pointer, or *options* is nonzero.
///
/// **ZX_ERR_NO_MEMORY** Failure due to lack of memory.
/// There is no good way for userspace to handle this (unlikely) error.
/// In a future build this error will no longer occur.
///
/// ## See also
///
/// - [`zx_eventpair_create()`]
/// - [`zx_handle_close()`]
/// - [`zx_handle_duplicate()`]
/// - [`zx_handle_replace()`]
/// - [`zx_object_signal()`]
/// - [`zx_object_wait_async()`]
/// - [`zx_object_wait_many()`]
/// - [`zx_object_wait_one()`]
///
/// [`zx_eventpair_create()`]: eventpair_create.md
/// [`zx_handle_close()`]: handle_close.md
/// [`zx_handle_duplicate()`]: handle_duplicate.md
/// [`zx_handle_replace()`]: handle_replace.md
/// [`zx_object_signal()`]: object_signal.md
/// [`zx_object_wait_async()`]: object_wait_async.md
/// [`zx_object_wait_many()`]: object_wait_many.md
/// [`zx_object_wait_one()`]: object_wait_one.md
Create(struct {
options uint32;
}) -> (resource struct {
out handle:EVENT;
}) error status;
};