Commodore CBM - Logical Files

The programmer makes up the logical file number. just as he does program
variable names; the logical file number may
be any number from 1 to 255. Once
opened. the logical file can
be used only for the type of operation specified by the
OPEN statement until the logical file is closed; then it becomes free to use again
in a different operation. A logical file may be opened only once before it is closed;
if a file
is opened twice before it is closed. a ?FILE OPEN error results. No more
than ten logical files may
be opened at the same time.
secondary address code a
secondary address code b
secondary address code a
secondary address code b
secondary address code a
secondary address code b
r-
UP 10 10 logical files
can
be open al one
lime.
OPEN-Iogical file number a
OPEN-Iogical file number b
OPEN-Iogical file number c
OPEN-Iogical file number d
OPEN-Iogical file number e
OPEN-Iogical file number f
OPEN-Iogical file number 9
OPEN-Iogical file number h
OPEN-Iogical file number i
OPEN-Iogical file number j
OPEN-Iogical file number k
OPEN-Iogical file number 1
OPEN-Iogical flle number m
OPEN-Iogical file number n
OPEN-Iogical file number 0
OPEN-Iogical flle number p
PEN-Iogical file number q
OPEN-Iogical file number r
OPEN-Iogical file number s
OPEN-Iogical file number 1
OPEN-Ioglcal file number u
OPEN-Iogical file number v
OPEN-Iogical file number w
OPEN-Iogical file number x
secondary address code a
secondary address code b
secondary address code a
secondary address code b
secondary address code a
secondary address code b
Figure 4-1. Logical Files
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