M command code

To move the subset pointer forward to the next segment after your current position, your program issues a call with the M command code.

Using the passbook account example, suppose that you want to post some, but not all, of the transactions, and that you want the subset pointer to be set to the first unposted transaction. The following command sets subset pointer 1 to segment B6, as shown in the figure below.
GU     Abbbbbbb(AKEYbbb
       Bbbbbbbb*R1M1

If the current segment is the last in the chain, and you use an M command code, IMS sets the pointer to 0.

Figure 1. Moving the subset pointer to the next segment after your current position
Shows two segment chains of 7 boxes labeled B1 to B7. The first chain represents