Note: UHL and UTL processing are user standard labels.
Under VSE, standard label write processing when FILABL=STD is specified in
the DTF includes:
┌──────┬──────┬─────┬────────────────┬─────┬──────┬─────┐│ VOL1 │ HDR1 │ TM │ Data Records │ TM │ EOV1 │ TM │└──────┴──────┴─────┴────────────────┴─────┴──────┴─────┘
for the first and intermediate volumes of a multivolume file, and
┌──────┬──────┬─────┬────────────────┬─────┬──────┬─────┬─────┐│ VOL1 │ HDR1 │ TM │ Data Records │ TM │ EOF1 │ TM │ TM │└──────┴──────┴─────┴────────────────┴─────┴──────┴─────┴─────┘
for the last volume of a multivolume file.
In addition to VSE formats, OS/390 standard labels, identified by the DD
parameter LABEL=(,SL), include HDR2, EOV2 and EOF2 labels. If these labels
are on input tapes under VSE, they are skipped; on output tapes, they are
overwritten. OS/390 accepts the absence of these labels when processing input
data sets.
OS/390 obtains information about the characteristics of a tape file (for example,
blocksize) from three different sources:
1. Thetape label (for labelled tapes)
2. TheDCB parameter of the DD job control statement (JCL) that identifies the
data set
3. TheDCB macro specification (assembler) or comparable high-level language
file specification within the source program. (Coding these in a program is
not recommended; that is, recoding and relinking of the program is required
when device type, blocksizes or other data set changes are desired.)
For output tapes, specifying the file characteristics via JCL specifications is
recommended. It provides flexibility by allowing OS/390 to make final device (in
this case, tape drive) assignments at job execution time.
VSE file-ids can be up to 17 characters in length, and do not have to be qualified;
that is, the 17 characters do not have to have any periods in the string of
characters. In OS/390, file names (data set names) must have qualifiers if more
than eight characters are used in the name (that is, a period must be used in the
file name with no more than eight characters in a qualifier). If VSE created
file-ids are longer than eight characters and unqualified, the files can be read in
OS/390 only by specifying their file-id in apostrophes. This is done in the JCL
DSN= parameter; for example, DSN=′payroll/datafile52134′.
If HDR2 tape labels are not present on data sets used as input to OS/390 (HDR2s
aren′t created by VSE systems), you must supply the
VOL1 volume label
HDR1 and HDR2 data set header label
EOV1 and EOV2 data set trailer labels (end of volume)
EOF1 and EOF2 data set trailer labels (end of data set)
UHL1 - UHL8 user header labels
UTL1 - UTL8 user trailer labels
104 VSE to OS/390 Migration Workbook