// Assert
        assertEquals(-1, actual);
    }

    @Test
    @DisplayName("Structure: DOS_ERROR_CODES is non-null with [code,status] pairs")
    void dosErrorCodesStructureIsValid() {
        // Arrange & Act
        int[][] table = DosError.DOS_ERROR_CODES;

        // Assert
        assertNotNull(table, "DOS_ERROR_CODES must not be null");