gtkTextIterBackwardLine: gtkTextIterBackwardLine
In RGtk2: R Bindings for Gtk 2.8.0 and Above

Description Usage Arguments Value Author(s)

Moves iter to the start of the previous line. Returns TRUE if iter could be moved; i.e. if iter was at character offset 0, this function returns FALSE. Therefore if iter was already on line 0, but not at the start of the line, iter is snapped to the start of the line and the function returns TRUE. (Note that this implies that in a loop calling this function, the line number may not change on every iteration, if your first iteration is on line 0.)