FindWindow error 183
Does anybody know what would cause the FindWindow
function to return the error:
ALREADY_EXISTS error (183)
I could understand a FILE_NOT_FOUND (2)
, but why would it return a 183
?开发者_StackOverflow
MSDN says, that FindWindow
and FindWindowEx
return NULL if the function fails and that you should check GetLastError
. It seems that this documentation is wrong. Take this code fragment:
SetLastError(12345);
HWND h = FindWindow(L"class_name_that_does_not_exist", nullptr);
cout << h << ' ' << GetLastError() << endl;
It will output
00000000 12345
So as you can see FindWindow
fails to set the last error. In your case this means that the ERROR_ALREADY_EXISTS
was the last error set before FindWindow
was called.
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