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Developing a python script in QGIS 2.2, I can run algorithms from the Processing plugin fine such as those from QGIS geoalgorithms and SAGA.
Can you do the same for the algorithm "Merge shapefiles to one" from the Vector menu and how can you call it from the Python console?
The "Merge shapefiles to one" algorithm is from the Ftools plugin.
Found a link which might be useful: Accessing QGIS plugins in Python?