[gclist] origin of "handle"

[Marc Feeley]

Hello.  I'm trying to find the origin of the word "handle" in the
domain of memory management.  The oldest reference I know is in the
MacOS "inside macintosh" manuals (around 1983).  In the MacOS handles
were used to refer to movable blocks of memory.  The handle's address
would never change, but the block of memory it points to could be
moved by the memory allocator.

Surely the concept has been around for a longer time ("all problems in
CS can be solved by adding an extra level of indirection"...).  Can
anyone point me to an older use of the term "handle"?

Marc