🚀 go-pugleaf

I'm extending a NOTES$COMMAND.TPU file secured from the supplier of the BBOARD
software, St.Peter's College.  I've taken the command sequence used there to
print a range of NOTES from within VAX Notes to a locally-connected printer,
and am trying to build a version of the command which extracts to a file for
downloading to a PC or MAC.  Everything works fine:

! Extract a (range of) notes to file

procedure local_extract
  local print_range;
  local extract_file;
on_error
endon_error;
if notes$x_notefile_ctx = "" then
  message ("You are not currently in a conference");
  return;
endif;
print_range := read_line("Enter range of notes to extract: ");
if length(print_range) = 0
  then
    if last_key = ctrl_z_key
      then
        return
      else
        print_range := "."
    endif
endif;
extract_file := read_line("Enter filename for extraction: ");
if length(extract_file) = 0
  then
    if last_key = ctrl_z_key
      then
        return
      else
        extract_file := "sys$login:notes_extract.tmp"
    endif
endif;
message ("Extracting to file " + extract_file + "...");
update(ALL);
notes$do_command("extract " + extract_file + " " + print_range);
endprocedure
define_key('local_extract', key_name('x', shift_key), "Extract to file",
  notes$kt_user_keys);

But now I'd like to extend it to determine if the filename specified already
exists.  If so, I want to give the option of
        (1) appending to the file,
        (2) creating a new generation of the file, or
        (3) backing up and choosing a different filename

Is there a builtin eve or tpu function that I can use to check to see if the
filename named in the "extract_file" variable already exists?  If not, being a
total novice at this kind of thing, does anybody have any suggested code
fragments?  I'm not looking to become a TPU/EVE programmer...my boss would not
approve of the time required ;-)

+-"Never Underestimate the bandwidth of a station wagon full of mag tapes"--+
| J.Lance Wilkinson ("Lance")            BitNet:    JLW@PSULIAS.BITNET      |
| Systems Design Specialist - Lead       InterNet:  JLW@PSULIAS.PSU.EDU     |
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