CLOSE #channel

   Synopsis:
      Closes a file channel

   Notes:
      Closes a file channel created with an earlier OPEN statement. When the
         Axbasic script halts, all file channels are automatically closed, but
         it's good practice to close a channel as soon as you no longer need it.

   Examples:
      ! Open a file channel, read a value, then close the channel
      OPEN #1: NAME "myfile.txt"
      INPUT #1: text$
      CLOSE #1
      END
