In this example, TRKCALC is coded to determine how many records of a given size with 10-byte keys fit on an IBM® 3380 track. After issuing the macro, the number of records is saved in NUMREC:

         TRKCALC  FUNCTN=TRKCAP,TYPE=UTYPE,R=1,K=10,DD=DL,             X
               MF=(E,(1))
         .
         .
         ST   0,NUMREC   SAVE NUMBER OF RECORDS
         .
         .
DL       DC   H'xxxx'    DATA LENGTH
UTYPE    DC   X'0E'
NUMREC   DS   F          MAX # OF RECORDS

In this example, TRKCALC is coded to determine whether another record can fit on a track of a 3380, given a track balance.

         TRKCALC  FUNCTN=TRKBAL,TYPE=UTYPE,R=REC,K=KL,DD=DD,           X
               BALANCE=BAL,MAXSIZE=YES,MF=(E,(1))
         .
         .
UTYPE    DC   X'0E'
REC      DC   X'xx'
KL       DC   X'xx'
DD       DC   H'xxxx'
BAL      DC   H'xxxx'