based on the example of use mplayer play the movie, I write down
sthing like
>\defineprogram[sample.data][sample.data.sh]
>\goto{\externalfigure[sample.data][width=0.48\textwidth]}[program(sample.data{})]
and the content of sample.data.sh is
>#!/bin/bash
> FILE=$(basename
[position][command][state]
# \definemainfield
\definemakeup[name][settings]
\definemarking[name][name]
# \definemeasure
# \defineoutput[name][specials]
\defineoverlay[names][command]
# \definepagebreak
\definepalet[name][name]
\definepapersize[name][dimenstions]
\defineparagraphs[name][op