我这样写，不对，还是可以重复运行
DECLARE LONG CreateMutex  IN Kernel32 STRING@, LONG, STRING@
DECLARE LONG GetLastError IN Kernel32
DECLARE LONG CloseHandle  IN Kernel32 LONG

szPrg  = PROGRAM()
hMutex = CreateMutex(NULL, 0, @szPrg)

IF GetLastError() = 183    && ERROR_ALREADY_EXISTS
    MESSAGEBOX(szPrg + " 不能重复运行")
    QUIT
ENDIF

CloseHandle(hMutex)