beautypg.com

Fxmto with fixed-length record format, Fxmto with variable-length record format – HP XP20000XP24000 Disk Array User Manual

Page 37

background image

About Cross-OS File Exchange Operations

2-19

Hitachi USP V Cross-OS File Exchange User’s Guide

FXmto with Variable-Length Record Format

Each variable-length record in a z/OS dataset includes a four-byte RL field and
the variable-length data entity. The record length defined for a variable-length

dataset equals the maximum allowable record length.

Note: If you want to be able to transfer the data back to the original z/OS
dataset later, you must use FXmto without padding and with delimiters.

No padding, no delimiters. Figure 2-11 shows an FXmto operation without
padding or delimiters for a variable-length source dataset. FCU extracts and
transfers only the data entities to the target file. The RL fields are not

transferred. The resulting length of each data entity in the target file is equal
to or less than the maximum record length minus four bytes (for the RL field).

Note: If you plan to transfer the data back to the original dataset later using
FXotm, use FXmto with delimiters.

Source Dataset

Open-System Target File

Record length

Record length – 4 bytes

RL Record 1: Data entity 1

Data entity 1

RL Record 2: Data entity 2

Data entity 2

RL Record 3: Data entity 3

Data entity 3

Figure 2-11

FXmto with Variable-Length Records: No Padding, No
Delimiters

With padding. Figure 2-12 shows an FXmto operation with padding. FXmto

with padding requires a variable-length source file and produces a fixed-length
target file. FCU adds padding to the source records as needed so that the
length of each record equals the maximum record length. FCU then extracts

and transfers the data entities with padding to the open-system target file.
The RL fields are not transferred. The resulting length of each data entity in
the target file equals the maximum record length minus four bytes (for the RL
field).

Note: If you use FXmto with padding, you will not be able to transfer the data
back to the original dataset later using FXotm.