guint delete_text ( GtkEntryBuffer* buffer, guint position, guint n_chars )
Deletes a sequence of characters from the buffer.
n_chars characters are deleted starting at
n_chars is negative, then all characters until the
end of the text are deleted.
n_chars are out of bounds, then they
are coerced to sane values.
Note that the positions are specified in characters, not bytes.
Position at which to delete text.
Number of characters to delete.