18 The SYSTEM Package

pointer-from-address

Function

Summary

Returns the object into which the given address is pointing.

Package

system

Signature

pointer-from-address address => object

Arguments

address: The address of the object to return. An integer.

Values

object: The object pointed to by address.

Description

Returns the object into which the given integer address is pointing. Note that this address may not be pointing into this object after a garbage collection, unless the object is static and is still referenced by another Lisp variable or object.

Example

CL-USER 1 > (setq static-symbol 
              (sys:in-static-area 
                 (make-symbol "THIS-SYMBOL")))
#:THIS-SYMBOL

CL-USER 2 > (sys:object-address static-symbol)
25754040

CL-USER 3 > (sys:pointer-from-address 25754040)
#:THIS-SYMBOL

CL-USER 4 > (eq * static-symbol)
T

CL-USER 5 >

See also

object-address