English: This source code demonstrates how a mine might occur in a COBOL program. Suppose the screen is invalid. Then after the first perform statement, control will go to the fix-error section. This requires the screen to be updated and will trigger the mine at the end of the update-screen section. Control could either return to the first perform statement or to the end of fix-error, where control will "fall-through" to update-screen before returning to the original perform statement.