IBM 5110 User Manual page 144

TYPE=:
Parameter and
Data Format
A
APL internal
blocked/ spanned
I
Character data
blocked/ spanned
U
Character data
unblocked/
unspanned
M
APL internal
blocked/ spanned
Once the DSVR function is used to retract a shared variable offer, the
shared variable becomes an ordinary variable.
A~"3+1+
A
The following chart summarizes the data file types for input/output
operations. Sequentially accessed data files require one shared
variable, and directly accessed data files require a pair of shared
variables (CTL/DAT). Records in the data files can be blocked and
spanned or unblocked and unspanned. Blocked and spanned records
can span sector boundaries. Unblocked and unspanned records cannot
span sector boundaries; that is, the record must be less than or equal
to the sector size and there is only one record per sector.
File Type
Displayed Using
the )LlB Command
Sequential Direct,
(OUT) (OUTF) Comments
8 10
• The 5110 defaults to TVPE=A if the parameter is not
specified.
·
For file type 10, all the records in the file must be the same
size and representation (character, binary, fixed point, or
floating point).
- - - -
,---
--
2 9
·
File types 2 and 9 can be read sequentially using an IN
operation.
•
File type 9 (blocked and spanned) uses less storage than
file type 10 for character data.
• For file type 9, all the records in the file must be the same
size.
9 or B9 • File types 9 and B9 can be read sequentially using an IN
operation.
·
File type B9 is the basis of exchange with other products.
• All the records in the file must be the same size.
8 15
•
For file type 15, all the records in the file must use the
same or less storage than the first record written to the file,
and records must be read or written one at a time.
I nput/Output Control 139