AT&T 6300 Programmer's Manual page 489

Syntax
variable
Remarks
VARPTR$
Function
Returns a character form of the memory
address of the variable.
v
ARPTR$ (variable)
is a variable existing in the program.
A value must be assigned to "variable" prior
to execution of VARPTR$. Otherwise, an
"Illegal function call" error results. Any type
of variable (numeric, string) may be used.
VARPTR$ returns a three-byte string in the
form:
byte 0
=
type
byte 1
=
low byte of address
byte 2
=
high byte of address
Note that type indicates the variable type:
2 integer
3 string
4 single-precision
8 double-precision
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