You can specify various member name for the copy operation.
If you specify TOMBR (*FIRST), the copy operation does
not specify a label identifier. Therefore, you must specify a label identifier
(LABEL parameter) on an OVRTAPF command. If you specify the special value
*FIRST, or *TAPF on the copy command, then the copy command uses the label
from the device file description.
If the from-file is tape, the copy command uses the from-file
label as the label for a tape to-file. If the to-file is a database file,
the command uses the nonblank characters to the extreme right of the from-file
label for the member name of the to-file. The command uses up to a maximum
of either 10 characters or to the period at the extreme right in the from-file
label. The copy operation uses only valid member names for a database to-file.
If the from-file is a tape file that is not labeled, then a to-file member or label name is created that corresponds to the data file on the tape from-file in the form of CPYnnnnn, where nnnnn is the tape sequence number of the data file.