Presidential veto in US legal system

The US Constitution mandates the President to sign the bills approved by the Congress. The president can, within a deadline of ten days, sign a bill approved by the Congress, which will result to a law. If the President rejects the bill within that deadline for any reason and returns to the House which it was originated, the President's action shall be considered as a regular veto. After reconsideration, the Houses may, with two-thirds of the votes of their members, insist on its previous resolution, in which case the president's veto will be ineffective and the congressional resolution becomes a law without President's sign. If the ten-day deadline passes and the president does not announce his signature or veto, while the congress is at a session, the bill becomes a law; however, if the congress is not in session, the bill will not become a law. In this case, the pocket veto has been taken. Therefore, a pocket veto is possible at the time of the intersession and final session closurs of congress, but it is not feasible and is contrary to the constitution at the time of intrasession closurs of congress. The Supreme Court has unequivocally proclaimed the partial veto of the approved bills as a constitutional violation.