TOPS-20 file-io

[JONL at MIT-MC (Jon L White)]

MERGEF loses.  If you use MACSYMA while **not** connected to
the <macsym> directory you will lose.  The following scenario
should describe the bug perfectly (prefix char of line indicates
who is typing at whom):
@CD <MACLISP>
@RUN LISP
%ALLOC ?
*N
%
%*
*(MERGEF '|FOO| '((DSK MACSYM) * FASL))
%((PS MACLISP) FOO FASL /0)

So the problem seems to be in the buggy code of FIL6BT that 
attempts to play around with GTJFN.