!
! Simple File I/O example
! Copies from file `infile' to file `outfile'
! 
let
	const INNAME ~ 
		[ 'i', 'n', 'f', 'i', 'l', 'e', chr(0), chr(0), chr(0), chr(0), 
		  chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0)];
	const OUTNAME ~ 
		[ 'o', 'u', 't', 'f', 'i', 'l', 'e', chr(0), chr(0), chr(0), 
		  chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0), chr(0)];
	var infile : Integer;
	var outfile : Integer;
	var c : Char;
	var eof : Boolean
in begin

	fopen(var infile, INNAME, false);

	if (infile < 0) then begin

		! error opening input file, message 'I!'
		put('I');
		put('!');
		puteol()

	end else begin

		fopen(var outfile, OUTNAME, true);

		if (outfile < 0) then begin

			! error opening output file, message 'O!'
			put('O');
			put('!');
			puteol()

		end else begin

			! both files open, begin copying
			feof(infile, var eof);
			while (\ eof) do begin
				fget(infile, var c);
				fput(outfile, c);
				feof(infile, var eof)
			end;
			fclose(outfile)

		end;

		fclose(infile)
	end
end