Commodore 1581 - Reading File Data: Using GET#

those data elements to be read back into a numeric variable by
INPUT# later, although file data errors may be avoided by reading all
data in as strings, and converting to numbers using the VAL () function
after the information is inside the computer.
For example, "N$ = RIGHT$(STR$(N)J£N(STR$(N))-1)" will
convert a positive number N into a string N$ without the usual leading
space for its numeric sign. Then instead of writing PRINT#5,N, you
would use PRINT#5,N$.
READING FILE DATA: USING GET#
The GET# statement retrieves data from the disk drive, one
character at a time. Like the similar keyboard GET statement in BASIC,
it only accepts a single character into a specified variable. However,
unlike the GET statement, it doesn't just fall through to the next
statement if there is no data to be gotten. The primary use of GET# is
to retrieve from diskette any data that cannot be read into an INPUT#
statement, either because it is too long to fit in the input buffer or
because it includes troublesome characters.
FORMAT FOR THE GET# STATEMENT:
GET#file#,variable list
where "file #" is the same file number given in the desired file's
current OPEN statement, and 'Variable list" is one or more valid BASIC
variable names. If more than one data element is to be input by a
particular GET# statement, each variable name must be separated
from others by a comma.
In practice, you will almost never see a GET or GET# statement
containing more than one variable name. If more than one character is
needed, a loop is used rather than additional variables. Also as in the
INPUT# statement, it is safer to use string variables when the file to be
read might contain a non-numeric character.
Data in a GET# statement comes in byte-by-byte, including such
normally invisible characters as the Carriage Return, and the various
cursor controls. All but one will be read properly. The exception is
CHR$(0), the ASCII Null character. It is different from an empty string
(one of the form A$ = ""), even though empty strings are often re
ferred to as null strings. Unfortunately, in a GET# statement, CHR$(0)
is converted into an empty string. The cure is to test for an empty
string after a GET#, and replace any that are found with CHR$(0)
instead. The first example below illustrates the method.
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