gtk-editable-insert-text (editable text position)

editable -- a gtk-editable widget
new-text -- a string with the text to append
position -- an integer with the position text will be inserted at

An integer with the position after the newly inserted text.

Inserts new-text into the contents of the widget, at position position.

Note that position is in characters, not in bytes. The function returns the position to point after the newly inserted text.