Write commands that do not operate in a Locate Record or Locate Record
Extended domain must be preceded by a search command that compares equal on
all bytes of the search field. The Locate Record Orient operation code does not
satisfy the search prerequisite for a write command.
No write command is defined for both single-track and multitrack forms. Write
Count, Key, and Data Next Track, Write Update Key and Data, and Write Update
Data are defined for multitrack form only. All other write commands are defined for
single-track form only.
Track Padding
Track padding fills out the remaining portion of a track with a special byte pattern
after format writing completes. Track padding begins after the gap following the
last field formatted on a track.
If a command other than a format write is chained from a format write and device
padding is used, the command can operate as a command that is not oriented.
That is, device padding does not establish index orientation. Therefore, if the
channel reconnects after index, the next command operates whenever reconnection
occurs.
Record Padding
If the CCW byte count for any write command is less than that required to fill the
record areas operated on by that command, the remainder of the record will be
filled with binary zeros if no exception condition (other than incorrect length
indication) is detected. If any other exception condition causes data transfer to be
terminated prematurely, any data received for the affected record is discarded and
that record is not formatted or updated.
Invalid Track Format
An attempt to write a record beyond the end of a track will result in Invalid Track
Format being reported in sense data following unit check status to the offending
write command.
Chapter 4. Command Descriptions
4-83
Содержание Multiprise 3000
Страница 1: ...S 390 Multiprise 3000 Enterprise Server R IBM Internal Disk Subsystem Reference Guide SA22 1025 00 ...
Страница 2: ......
Страница 3: ...S 390 IBM Internal Disk Subsystem Reference Guide SA22 1025 00 ...
Страница 32: ...2 12 Internal Disk Subsystem Reference Guide ...
Страница 38: ...3 6 Internal Disk Subsystem Reference Guide ...
Страница 182: ...4 144 Internal Disk Subsystem Reference Guide ...
Страница 198: ...5 16 Internal Disk Subsystem Reference Guide ...
Страница 214: ...6 16 Internal Disk Subsystem Reference Guide ...
Страница 234: ...A 10 Internal Disk Subsystem Reference Guide ...
Страница 238: ...B 4 Internal Disk Subsystem Reference Guide ...
Страница 243: ...4 lease the Code or any copy of it Appendix C Warranties C 5 ...
Страница 244: ...C 6 Internal Disk Subsystem Reference Guide ...
Страница 248: ...D 4 Internal Disk Subsystem Reference Guide ...
Страница 254: ...X 6 Internal Disk Subsystem Reference Guide ...
Страница 263: ......
Страница 264: ...IBM Printed in the United States of America on recycled paper containing 10 recovered post consumer fiber SA22 1 25 ...