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User_Message_Recorded

Programmer's Reference Manuals
» Part 7 - The Desktop
» The Window Manager
» SWI Calls
» Wimp_Poll
» Reason Codes
» User_Message_Recorded

User_Message_Recorded

(Reason Code 18)
Exit
Block
+0 Length of block
+4 Handle of sender
+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:

  1. this specific task
  2. a specific window belonging to this task
  3. 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

  • Message Codes
  • Reason Codes
  • User_Message
  • User_Message_Acknowledge
  • Wimp_Poll
Revised on June 9, 2009 20:55:55 by Alan Robertson (52)? (127.0.0.1)
Edit | Back in time (1 revision) | See changes | History | Views: Print | Source | Linked from: Poll Mask, User_Message, User_Message_Acknowledge, Message_DataLoad, Message_RAMFetch, Message_RAMTransmit, Reason Codes

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