Label definitions and organization

IBM standard labels are 80-character records written in the density specified using JCL. Cartridge and 9-track tape label records are recorded in EBCDIC. Seven-track tape label records are recorded in BCDIC, even parity, translate on. The first 4 characters are always used to identify the labels:

Label Identifier: Label Description
VOL1: Volume label
HDR1 and HDR2: Data set header labels
UHL1 through UHL8: User header labels
EOV1 and EOV2: Data set trailer labels (end-of-volume)
EOF1 and EOF2: Data set trailer labels (end-of-data-set)
UTL1 through UTL8: User trailer labels

The header and trailer labels use identical formats; therefore, there are only four different label formats. These formats are described later in this section. The four types of label formats are:

Standard volume label (identified as VOL1)
Standard data set label 1 (identified as HDR1, EOV1, or EOF1)
Standard data set label 2 (identified as HDR2, EOV2, or EOF2)
Standard user label (identified as UHL1-UHL8 or UTL1-UTL8)

Figure 1 and Figure 2 show the positions of the labels with various tape volume organizations. A tape with IBM standard labels must contain a volume label and data set labels. User labels are optional.

Figure 1. Volume organizations with IBM standard labels (single data set)

Figure 2. Volume organizations with IBM standard labels (multiple data sets)