CA Dynam for VSE User Guide

Basic Components
To request space for a file not defined in the Catalog, use an EXTENT Job
Control statement. Indicate in that statement a relative track (or block) value
of 1 or the value specified for TRIGGER in the DYNAM/D option record. The
trigger indicates that CA Dynam/D should allocate the file.
For example,
// JOB SINGLE EXTENT EXAMPLE
// DLBL SDDOUT,'DISK.FILE',2099/360
// EXTENT SYS006,POOL01,1,0,1,8
// EXEC PROGRAM
CADD002I ALLOCATED FILE=SDDOUT SYS006=202 SYSWK1 X=0/12/8
Note: Relative track value = 1 and number of tracks to allocate = 8
CA Dynam/D does not allocate any EXTENT not defined with the TRIGGER
value from the DYNAM/D option record. Instead, the requested EXTENT is
passed directly to the standard operating system OPEN routine.
A Job Control exit is provided with CA Dynam/D. This exit will automatically
change the EXTENT statements in any supplied Job Control stream to force
dynamic allocation.
For a file defined in the CA Dynam Catalog File, the EXTENT statement is
omitted; space is allocated based on the specification in the Catalog entry for
that file.
For example,
// JOB GENERATE FILE FROM CATALOG
// DLBL SDDOUT,'DISK.FILE'
// EXEC PROGRAM
CADD002I ALLOCATED FILE=SDDOUT SYS001=202 DOSVS2 X=0/6/8
CADD022I RELEASED 00008 TRACKS FILE=SDDOUT VOL=SYSWK1
Note that the disk file can be defined in the Catalog with a specific number of
tracks (CKD devices), blocks (FBA devices), cylinders, or records (logical
allocation).
If a number of records is defined, CA Dynam/D will calculate the correct
number of tracks or blocks for the allocation based upon the blocking factor in
use and the device type.
If a number of cylinders is defined, CA Dynam/D will allocate the requested
number of cylinders or cylinder equivalents on the allocated device type.
Chapter 4: Disk File Management 4–3