Commodore 1581 - Commas and Colons in File Handling

INPUT# statement, but may also have been caused by errors in a
PRINT# statement when the file was written.
"String Too Long" Error
A BASIC string may be up to 255 characters long, although the
longest string you can enter via a single Input statement is just under
two lines of text. This lower limitation is due to the size of the input
buffer in Commodore's serial bus computers. The same limit applies
to INPUT# statements. If a single data element (string or number)
being read from a disk file into an INPUT# statement contains more
than 88 (BASIC 2) and 160 (BASIC 7) characters, BASIC will halt with a
"STRING TOO LONG ERROR."
"File Data" Error
The other error message "FILE DATA ERROR" is caused by at
tempting to read a non-numeric character into a numeric variable. To
a computer, a number is the characters 0 through 9, the " + " and " - "
signs, the decimal point (.), the SPACE character, and the letter "E"
used in scientific notation. If any other character appears in an IN-
PUT# to a numeric variable, "FILE DATA ERROR" will be displayed
and die program will halt. The usual causes of this error are a mis
match between the order in which variables are written to and read
from a file, a missing carriage return within a PRINT# statement that
writes more than one data item, or a data item that includes either a
comma or a colon without a preceding quotation mark. Once a file
data error has occurred, you should correct it by reading the data item
into a string variable, and converting it back to a number with the
BASIC VAL() statement after removing non-numeric characters with
the string functions described in your computer user's manual.
Commas (,) and Colons (:)
As suggested before, commas and colons can cause trouble in a
file, because they delimit (end) the data element in which they appear
and cause any remaining characters in the data element to be read into
the next INPUT# variable. They have the same effect in an INPUT
statement, causing the common "EXTRA IGNORED" error message.
However, sometimes you really need a comma or colon within a data
element, such as a name written as "Last, First." The cure is to precede
such data elements with a quotation mark. After a quotation mark, in
either an INPUT or INPUT# statement, all other characters except a
carriage return or another quotation mark are accepted as part of the
current data element.
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