clear_messageclear_messageClearMessageclear_messageClearMessageClearMessage (Operator)

Name

clear_messageclear_messageClearMessageclear_messageClearMessageClearMessage — Close a message handle and release all associated resources.

Description

clear_messageclear_messageClearMessageclear_messageClearMessageClearMessage closes a message handle MessageHandleMessageHandleMessageHandleMessageHandleMessageHandlemessageHandle that was previously opened with create_messagecreate_messageCreateMessagecreate_messageCreateMessageCreateMessage or dequeue_messagedequeue_messageDequeueMessagedequeue_messageDequeueMessageDequeueMessage. 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_messageClearMessageclear_messageClearMessageClearMessage call, passing them as a tuple to the MessageHandleMessageHandleMessageHandleMessageHandleMessageHandlemessageHandle parameter.

Attention

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

Parallelization

Multithreading type: reentrant (runs in parallel with non-exclusive operators).
Multithreading scope: global (may be called from any thread).
Processed without parallelization.

Parameters

MessageHandleMessageHandleMessageHandleMessageHandleMessageHandlemessageHandle (input_control) message(-array) → (integer)

Message handle(s) to be closed.

Number of elements: MessageHandle >= 1

Restriction: MessageHandle != 0

Example (HDevelop)

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

Result

If the message handle(s) passed to the operator are valid, clear_messageclear_messageClearMessageclear_messageClearMessageClearMessage returns 2 (H_MSG_TRUE). Otherwise an exception is raised. If a tuple of handles is passed and some of them are invalid, clear_messageclear_messageClearMessageclear_messageClearMessageClearMessage attempts to clear as many handles from the tuple as possible before reporting the error.