setting scroll parameters

[Robert Roebling <roebling ruf uni-freiburg de>]

  Good day,

I would like to set the relevant parameters of a scrolledwindow
directly, mainly (for x and y respectively)

- the scrolling unit (=step_increment ?)
- the current position (=pos ?)
- the possible range (= upper/lower ?)
- the page unit (=page_increment)

This would e.g. have to be done, when inserting a new line into
a text document (which would change range).

I thought (from reading the source) that I might use

gtk_viewport_set_vadjustment( scrolledwindow->viewport )

for that purpose, but this only caused the viewport not to
react to the scrollbar action any longer (I have not yet
fully understood the idea behind that, but that's a different
question).

     Thank you in advance and regards,

                Robert Roebling