AT&T 6300 Programmer's Manual page 269

Syntax
Remarks
Example
FRE
Function
Returns the number of bytes in memory not
being used by GWBASIC.
FRE(du~my)
Strings in GWBASIC have variable lengths,
changing each time you assign a value. This
dyn~mic
manipulation of strings can cause
the
~tring
space in memQry to become
fragmented.
The free function can reorganize the, stripg
space in memory. This housekeeping
consolidates the free space.
The argument to FRE is a dummy argument.
Be
pati~~t:
housekeeping may take 1 to
1-112
minutes.
GWBASIC, itself, initiates p.ousekeeping
when free memory is used up.
If
you are doing
extensive manipulation of variable length
strings useFRE(" ") periodically.
PRINT FRE(O)
14542
O~
7-113