Every program that executes is assigned two program attributes: an addressing mode (AMODE) and a residency mode (RMODE). Programmers can specify these attributes for new programs. Programmers can also specify these attributes for old programs through reassembly, linkage editor PARM values, linkage editor MODE control statements, or loader PARM values. MVS™ assigns default attributes to any program that does not have AMODE and RMODE specified.