After you've processed the callback call, you should use Call, passing it the value returned by Get - the callback. This tells System to return from the callback. If you've specified a source for the return "parameter" when the callback was created, you should fill that source with the appropriate return value. Callbacks are not automatically freed, don't forget to free it after you've finished using it.
+After you've processed the callback call, you should use Call, passing it the value returned by Get - the callback. This tells System to return from the callback. Destination of the return "parameter" must be cleared prior to calling a function, to avoid false detection of a callback call. If you've specified a source for the return "parameter" when the callback was created, you should fill that source with the appropriate return value. Callbacks are not automatically freed, don't forget to free it after you've finished using it.
SetPluginUnload alwaysoff System::Get "(i .r0, i .r1) isR0" @@ -381,6 +381,7 @@ loop: StrCmp $R0 "callback1" 0 done DetailPrint "UseCallback passed ($0, $1) to the callback" Push 1 # return value of the callback + StrCpy $R0 "" # clear $R0 in case there are no more callback calls System::Call $0 # tell system to return from the callback Goto loop done: