plotting free form ascii data

[patrick(at)es.ucsc.edu (Patrick McEnaney)]

Greetings-

I'm attempting to write a gui script to plot free form ascii data.
I've utilized the ascii_template and read_ascii functions but the
program hangs after hitting finished on the ascii_template gui and
returns an error:

% READ_ASCII: File name must be a string.
% Execution halted at:  READ_ASCII        792
/auto/soft/idl/idl_5.4/lib/read_ascii.pro
%                       PLOTINTERACTIVE_READ   31
/home/swifs/training/idlinterm/interplot2.pro
%                       XMANAGER_EVLOOP_STANDARD  478
/auto/soft/idl/idl_5.4/lib/xmanager.pro
%                       XMANAGER          708
/auto/soft/idl/idl_5.4/lib/xmanager.pro
%                       PLOTINTERACTIVE   209
/home/swifs/training/idlinterm/interplot2.pro
%                       $MAIN$

I'm using a variable name xdata, very simple and yes, a string. What
gives?

Also, I'm curious as to the best way to pass this to the PLOT
function?

Any suggestions welcome,

Patrick