gboolean gtk_text_buffer_get_iter_at_line ( GtkTextBuffer* buffer, GtkTextIter* iter, int line_number )
iter to the start of the given line.
line_number is greater than or equal to the number of lines
buffer, the end iterator is returned.
Iterator to initialize.
The argument will be set by the function. The data is owned by the caller of the function.
Line number counting from 0