Commodore 1581 - Page 51

where "file #" is the same file number given in the desired file's
current OPEN statement. During any given access of a particular file,
the file number must remain constant because it serves as a shorthand
way of relating all other file-handling commands back to the correct
OPEN statement. Given a file number, the computer can look up
everything else about a file that matters.
The "data list" is the same as for a PRINT statement - a list of
constants, variables and/or expressions, including numbers, strings or
both. However, it's better if each PRINT# statement to disk include
only one data item. If you wish to include more items, they should be
separated by a carriage return character, not a comma. Semicolons are
permitted, but not recorded in the file, and do not result in any added
spaces in the file. Use them to separate items in the list that might
otherwise be confused, such as a string variable immediately following
a numeric variable.
-NOTE
Do not leave a space between PRINT and #, and do not
abbreviate the command as ?#. The correct abbreviation for
PRINT# is pR.
EXAMPLES:
To record a few grades for John Paul Jones, using a sequential disk file
#1 previously opened for writing, use:
200 FOR CLASS = 1 TO COURSES
210 PRINT#1,GRADE$(CLASS)
220 GOSUB 59990:REM CHECK FOR DISK ERRORS
320 NEXT CLASS
assuming your program includes an error check subroutine like the
one in the last chapter.
In using PRINT#, there is an exception to the requirement to
check for disk errors after every file-handling statement. When using
PRINT#, a single check after an entire set of data has been written will
still detect the error, so long as the check is made before any other
file-handling statement or disk command is used. You may be familiar
with PRINT statements in which several items follow each other:
400 PRINT NAME$,STREET$,CITY$
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