User's Manual

XEROX LASER PRINTING SYSTEMS TAPE FORMATS MANUAL 5-1
5. 5IBM POWER/VS and POWER/
VSE tape organization
This chapter describes the IBM POWER/VS and POWER/VSE tape
organization. It also includes example file formats and a sample JSL.
Tape formats
The Xerox printing system accepts tapes produced by IBM DOS/VS
POWER and DOS/VSE POWER as illustrated in figure 5-1. These
tapes have no labels per se; however, the first and last blocks of a
file, which are identical, have a special length and content and, in a
limited sense, act as labels. Figure 5-2 presents an example of one
such special block or POWER/VS.
File formats
A tape mark precedes the first file on the tape. A single tape mark
separates files, and two tape marks end the tape. A tape mark
encountered in conjunction with an end-of-tape reflector denotes an
end-of-volume condition. (Refer to figure 5-1.)
For POWER VS, the file consists of one 152-byte special block,
followed by data blocks as described below in the section “Data
formats.” The last block in the file is another 152-byte special block.
For POWER/VSE, both special blocks are 184 bytes long, although
their format remains the same otherwise.
For POWER/VSE II, both special blocks are 216 bytes long, although
their format remains the same otherwise.