[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName={pf}\My Program
OutputDir=userdocs:Inno Setup Examples Output

[UninstallRun]
Filename: "calc.exe"; Parameters: "-f {code:GetUninstFilePath}"

[Code]
function GetUninstFilePath(Value: string): string;
begin
  Log('GetUninstFilePath');
end;