EOF (channel)

   Synopsis:
      Tests whether a file channel has reached the end of its file

   Notes:
      Tests the file channel created with an earlier OPEN statement. Returns 1
         if the file channel is open, and has reached the end-of-file. Returns 0
         if the the file channel is open, but has not reached the end-of-file
         (or if the file channel is closed).

   Examples:
      ! Read all the data in the file
      OPEN #5: NAME "data.txt", CREATE OLD, ACCESS INPUT
      IF EOF(5) = 1 THEN
         PRINT "File is empty!"
      ELSE
         ! Read data until EOF() returns 1
         DO
            INPUT #5: a$
            PRINT a$
         UNTIL EOF(5) = 1
      END IF
      END
