User's Manual

UNIVAC SERIES 70 (US70) MAGNETIC TAPE ORGANIZATION
XEROX LASER PRINTING SYSTEMS TAPE FORMATS MANUAL 6-5
Trailer label sets
File trailer labels
The first label of a trailer label set is called the standard trailer label.
This is either an end-of-file (ECF1) label or an end-of-volume (EOV1)
label. An end-of-file label indicates the end of a given file; an end-of-
volume label indicates the end of useful data on a tape volume. The
contents of the standard trailer label are contained in table 6-6.
In addition to the standard trailer label, the user may specify up to
seven additional file trailer labels, EOF2 through EOF8 or EOV2
through EOV8. These labels, if used, would follow the standard trailer
label. Their contents are shown in table 6-7.
Table 6-6. Standard file trailer label format
Field
Character
position(s)
Name Length Description
1 1-3 Label identifier 3 EOF=End-of-file trailer label
EOV=End-of-volume trailer label
2 4 File trailer label number 1 1
3-11 5-54 Same as corresponding
fields in file header label
50 Same as corresponding fields in file header
label
12 55-60 Block count* 6 Indicates the number of data blocks written on
the file from the last file header label to the first
file trailer label, excluding tape marks and
checkpoint records.
13 61-73 Same as corresponding
fields in file header label
13 Same as corresponding fields in file header
label
14 74-80 Same as corresponding
fields in file header label
7 Same as corresponding fields in file header
label
* Field 12 is used by the operating system.
Table 6-7. File trailer label format
Field
Character
position(s)
Name Length Description
1 1-3 Label identifier 3
EOF=End-of-file trailer label
EOV=End-of-volume trailer label
2 4 File trailer label number 1 2 through 8 in ascending sequence within the
EOF set or EOV set.
3 5-80 Undefined 76 Reserved