Can Inkscape Portable support Dia Portable?

The relevant lines I see from share/extensions/dia.inx are:

    <dependency type="executable" location="extensions" _description="The dia2svg.sh script should be installed with your Inkscape distribution.  If you do not have it, there is likely to be something wrong with your Inkscape installation.">dia2svg.sh</dependency>
    <dependency type="executable" _description="In order to import Dia files, Dia itself must be installed.  You can get Dia at http://live.gnome.org/Dia">dia</dependency>

dia2svg.sh exists in the source repository, but not in Windows (because sh files have no value on Windows, so they're not included).

#! /bin/sh

rc=0

# dia version 0.93 (the only version I've tested) allows `--export=-', but then
# ruins it by writing other cruft to stdout.  So we'll have to use a temp file.
# dia 0.95 removes --export-to-format but still allows -t.
TMPDIR="${TMPDIR-/tmp}"
TEMPFILENAME=`mktemp 2>/dev/null || echo "$TMPDIR/tmpdia$$.svg"`
dia -n --export="${TEMPFILENAME}" -t svg "$1" > /dev/null 2>&1 || rc=1

cat 

This should be converted to a Python file so it can work cross-platform. Can you comment on their usage of dia? Check if this works: put the following code in dia2svg.py in InkscapePortable\App\Inkscape\share\extensions and change dia.inx to reference it instead of dia2svg.sh. You'll also need to put DiaPortable\App\Dia\bin in the PATH (edit Inkscape's launcher.ini if that's easiest for you).

import sys
from run_command import run

run('dia -n --export="%%s" -t svg "%s"' % sys.argv[-1].replace('%', '%%'), 'dia')

[Updated from original: swapped %s and %%s]