Invoking IDF

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At the TSO/E READY prompt allocate the required data sets: 
ALLOC FI (ASMLANGX) DS('<myid>.ASMLANGX') SHR
TSOLIB ACT DS('<myid>.LOAD')
Invoke IDF by entering: 
  ASMIDF ASMMSAMP

Wait until the initial IDF panel is displayed, and then continue at Running IDF on a sample program.