User_Message_Recorded (changes)
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WindowManager
» SWI Calls
» Wimp_Poll
» Reason Codes
» User_Message_Recorded
User_Message_Recorded
(Reason Code 18)
| Exit | |
|---|---|
| Block | |
| +0 | Length of block |
| +4 | |
| +8 | My ref (senders reference number for this message) |
| +12 | Your ref (senders reference number for a previous message, if this a reply, otherwise 0) |
| +16 | Message Code |
| +20 | … data… |
Use
This code is returned from Wimp_Poll and indicates that another task has broadcast a message to any of the following:
- this specific task
- a specific window belonging to this task
- to all tasks
Notes
The message code determines the meaning of the message sent.
Unlike User_Messages, tasks that send this type of message can accept an acknowledgement message that the message was received.
A task can acknowledge the message by calling Wimp_SendMessage with the event code of 19 (User_Message_Acknowledge). Your_ref should be set to the original code sent (my_ref). This will prevent the sender from receiving its original message back from the Wimp with event code 19.
Another method of acknowledging a message is to send a reply message using event code User_Messages or User_Message_Acknowledge again with your_ref parameter set to the original message’s my_ref.
Both types of acknowledgement must take place before the next call to Wimp_Poll.
A task that does not understand a message code should simply ignore it. Tasks should not respond to messages for no reason.
See also
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