HP Business BASIC/XL Reference Manual - HP 3000 MPE/iX Computer Systems - Edition 1 (32715-90001)

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| BDATA | 1242 | HP Business BASIC/V Data |
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| BDTXL | 1248 | HP Business BASIC/XL Data |
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| BBNCM | 1249 | MPE/V binary file. |
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The filecode associated with each of the data files is used to identify
whether the file stores information in the MPE/V or MPE XL format. When
the file is opened by HP Business BASIC/XL, the file code is used to
determine the data storage format. If the file code indicates that the
file is was created on MPE/V, all the subsequent work of floating-point
real data conversion is done automatically. Therefore, it is possible to
share data among MPE XL native mode applications and existing programs
not yet migrated from compatibility mode. However, if the data file is
only intended for native mode programs and the data file was created
on MPE/V or in compatibility mode, run the conversion program
BBCTMPEV.PUB.SYS to avoid the performance impact of data conversion.
File Input and Output
File input and output (I/O) statements read input from and write output
to data files. The following input statements are available:
LINPUT
MAT READ
READ
The following output statements are available:
PRINT
UPDATE
In addition, the CATALOG statement is used to display directory
information about specified files. All of these statements are explained
in chapter 4.
Each data file has a record pointer and a word pointer associated with
it. A BASIC DATA file has a datum pointer as well:.
record pointer Indicates the next record to be read or written.
word pointer Indicates the next word (within the next record) to be
read or written.
datum pointer Indicates the next datum to be read or the next place
to write a datum.
After any file I/O operation, the record, word, and datum pointers
advance to the next respective record, word, or datum depending on the
type of I/O operation. The POSITION statement positions the record
pointer at a specified record. The ADVANCE statement moves the record
pointer forward or backward. These statements are defined in chapter 4.
Regardless of file type, a file I/O operation can be:
sequential Sequentially reads or writes to the record in the file
indicated by the position of the record pointer.
direct The record pointer is moved directly to a specific