| BOOL InSendMessage(void) |
The InSendMessage function specifies whether the current window procedure is processing a message that was sent from another task by a call to the SendMessage function.
This function has no parameters.
The return value is nonzero if the window procedure is processing a message sent to it from another task by the SendMessage function. Otherwise, the return value is zero.
Applications use the InSendMessage function to determine how to handle errors that occur when an inactive window processes messages. For example, if the active window uses the SendMessage function to send a request for information to another window, the other window cannot become active until it returns control from the SendMessage call. The only method an inactive window has to inform the user of an error is to create a message box.