15.64.24.4  Filename   - The  file  specification  may  include device and
directory.  If the filename contains a semicolon ";", or begins with  "V_"
or  "S_"  or  a  special  character  such  as a dollar sign "$" it must be
enclosed in quotes or apostrophes "'".  For example you may get the sample
input file.
     TD:SET FILE INPUT TOPDRAWER_ROOT:[EXAMPLES]TDINTRO

This  is  a  modification  of the original Topdrawer syntax.  The original
required a Fortran unit number.  By performing a  logical  assignment  you
may simulate the original syntax.  For example:
     $ ASSIGN FOR009.DAT "9"
defines 9 as the usual input on unit 9.