CLOSE

Action: This statement shuts off any data file or channel to a device. The file number is the same as when the file or device was OPENed (see OPEN statement and the section on INPUT/OUTPUT programming). When working with storage devices like cassette tape and disks, the CLOSE operation stores any incomplete buffers to the device. When this is not performed, the file will be incomplete on the tape and unreadable on the disk. The CLOSE operation isn't as necessary with other devices, but it does free up memory for other files. See your external device manual for more details.

   10 CLOSE 1
   20 CLOSE X
   30 CLOSE 9*(1+J)

CLR

Action: This statement makes available RAM memory that had been used but is no longer needed. Any BASIC program in memory is untouched, but all variables, arrays, GOSUB addresses, FOR...NEXT loops, user-defined functions, and files are erased from memory, and their space is mode available to new variables, etc.