clear_messageT_clear_messageClearMessageClearMessageclear_message (算子)

名称

clear_messageT_clear_messageClearMessageClearMessageclear_message — 关闭消息句柄并释放所有相关资源。

签名

clear_message( : : MessageHandle : )

描述

clear_messageclear_messageClearMessageClearMessageClearMessageclear_message closes a message handle MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle that was previously opened with create_messagecreate_messageCreateMessageCreateMessageCreateMessagecreate_message or dequeue_messagedequeue_messageDequeueMessageDequeueMessageDequeueMessagedequeue_message。Any resources owned by the message, in particular the tuple or object data stored in the message, will be released.

Multiple message handles can be closed in a single clear_messageclear_messageClearMessageClearMessageClearMessageclear_message call, passing them as a tuple to the MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle parameter.

注意

The handle(s) must not be used again after being invalidated using clear_messageclear_messageClearMessageClearMessageClearMessageclear_message. Using an invalid handle results in undefined behavior.

执行信息

多线程类型：可重入（与非独占算子并行运行）。
多线程作用域：全局（可从任何线程调用）。
未采用并行化处理。

此算子修改后续输入参数的状态：

MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle

在执行此算子时，若该参数值需在多个线程间使用，则必须对其访问进行同步。

参数

MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle (输入控制，状态被修改) message(-array) → (handle)

Message handle(s) to be closed.

元素数量： MessageHandle >= 1

限制： MessageHandle != 0

示例（HDevelop）

MessageHandles := []
for idx := 0 to 4 by 1
  create_message (MessageHandle)
  MessageHandles[idx]:= MessageHandle
endfor
* ...

结果

If the message handle(s) passed to the operator are valid, clear_messageclear_messageClearMessageClearMessageClearMessageclear_message 返回 2 ( H_MSG_TRUE )。否则将抛出异常。 If a tuple of handles is passed and some of them are invalid, clear_messageclear_messageClearMessageClearMessageClearMessageclear_message attempts to clear as many handles from the tuple as possible before reporting the error.

可能的前趋

create_messagecreate_messageCreateMessageCreateMessageCreateMessagecreate_message, dequeue_messagedequeue_messageDequeueMessageDequeueMessageDequeueMessagedequeue_message

另见

create_messagecreate_messageCreateMessageCreateMessageCreateMessagecreate_message, set_message_tupleset_message_tupleSetMessageTupleSetMessageTupleSetMessageTupleset_message_tuple, get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple, set_message_objset_message_objSetMessageObjSetMessageObjSetMessageObjset_message_obj, get_message_objget_message_objGetMessageObjGetMessageObjGetMessageObjget_message_obj, set_message_paramset_message_paramSetMessageParamSetMessageParamSetMessageParamset_message_param, get_message_paramget_message_paramGetMessageParamGetMessageParamGetMessageParamget_message_param, enqueue_messageenqueue_messageEnqueueMessageEnqueueMessageEnqueueMessageenqueue_message, dequeue_messagedequeue_messageDequeueMessageDequeueMessageDequeueMessagedequeue_message

模块

基础

算子