Sharp MZ-700 - Sequential Access File Control

18
DISK BASIC
Sequential Access File }
data file
BASIC Text Files }
L .. __ --:---r-------. program file.
_ Machine Language
Program Files
As the various file control commands are explained, first the preparation method, the
use, and the features of the 2 types of data files
will be explained, followed by an
explanation of the use of the CHAIN and
SWAP commands of the program files.
1.4 Sequential Access File Control
Sequential access files are data files in which the registration or read-out of data is in
the sequential access format. The sequential access format is, as mentioned previously,
a format
in which access to the data is in sequential order from the heading.
The method of making a data
file on a cassette file has already been explained in the
BASIC manual for the MZ-IZ013B. Sequential access for the DISK BASIC is exactly
the same except that the
file is made on the disk rather than a cassette. Naturally, the
access speed
is much faster, and, because several new file control commands can be
used for disk access, the breadth of useful functions for
file management is also
enlarged.
First,
we will compare the composition of sequential access commands for DISK
BASIC
and for CASSETTE BASE BASIC.
File registration (data write-in)
DISK BASIC
CASSETTE BASE BASIC
File open command WOPEN #n, "fjJename" WOPEN "filename"
Data write-in command PRINT #n, data
PRINTIT data
File close command CLOSE #n
CLOSE
Cancel command
KILL #n
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