Control Data Corporation 3300 Reference Manual page 28

60229400
If alternating tape units are to be used, each must be given a unique dsi.
Each file on a multi -file reel must have the same dsi. System files do not
requi re dsi.
Examples:
SELECT PAY-FILE ASSIGN TO TAPE AI, TAPE B2.
SELECT PAY-FILE ASSIGN TO DISK MSOl.
When a file is assigned to hardware names TTY and CRT, a second identifier
code, terminal unit identifier, must follow the dsi. (When the hardware-name
is TTY or CRT, only one hardware-name may be specified.) The terminal
unit identifier (tui) is a 1-4 character alphanumeric code used by MASTER
and the input-output control system to determine the local terminal unit as-
sociated with the assigned file. This identifier must match the code ass.igned
to the device when it is entered into the MASTER operating system hardware
unit table. For further information concerning the tui, refer to the MASTER
2.0 Reference Manual Pub. No. 60213600 and applicable installation procedures
documentation.
Examples:
SELECT TWX-FILE ASSIGN TO TTY ABS AOOl.
SELECT DISPLAY-FILE ASSIGN TO CRT DEF BOlO.
All equipment assigned, except TTY and CRT, must be scheduled on the
$SCHED card. Additionally, if the system printer, reader or punch are
to be used directly by the program they must be preempted from MASTER
with a $DIRECT card. (See Section 7, Source Program Preparation, Com-
pilation and Execution) .
SCRATCH files are automatically allocated by the I-O control system in the
system scratch file area. These files exist only for the duration of the job
and are released by MASTER at the end of each job. They may be processed
and used in all respects as a sequential mass storage file might be used.
Scratch area for these files must be scheduled with the $SCHED card (section
7.3.2) .
If file-name-1 is a file, only the ASSIGN clause can follow the key word
SELECT in the FILE-CONTROL paragraph (section 4.7.24, Sort).
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