TRKBAL macro - is type 3, gets no lock.
Calls module IGC0002E.
DDNAME | cccccccc | Name of the associated DD statement. |
DCBFDAD | xxxxxxxx | Full direct access address (MBBCCHHR) from the DCB that is pointed to by R1. |
DCBTRBAL | xxxx | Track balance (number of bytes remaining on the current track after a write; negative if no bytes remain). |