TOPS-20 PASCAL Language Manual - Bitsavers

CHAPTER 7
INPUT AND OUTPUT
This chapter describes input and output (I/O) for PASCAL on TOPS-20.
PASCAL provides predefined procedures to perform input and output to
file variables. These procedures are divided into the following
categories:
General Procedures
• OPEN -- associates R file with specified characteristics
• CLOSE -- closes a file
• FIND -- performs direct access to file components
Input Procedures
• RESET -- opens a fiJe and prepares it for input
• GET -- reads a file component into the file buffer variable
• READ -- reads a file component into R specified variable
• READLN -- reads a line from a text file
Output Procedures
• REWRITE -- truncates a file to length zero and prepares it
for output
• PUT -- writes the contents of the file buffer variable into
the specified file
• WRITE -- writes specified values into a file
• WRITELN -- writes a line into a text file
• LINELIMIT -- terminates program execution after a specified
number of lines have been written into a text file
• PAGE -- skips to the next page of a text file
In addition, you can use the predefined functions EOF and EOLN with
text files.
The following sections describe:
• PASCAL file characteristics
• PASCAL record formats
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