title: WinExec Return 0x21, But what exactly it means?
body: <p>When call WinExec to run a .exe, I get return value 0x21. <br />
  According to MSDN, a return value greater than 31 (0x1F) means function succeeds. <br />
  But what does it mean of 0x21, Why it didn't return other value to me?</p>