How to request Facebook publish_actions permission during login in iOS

To request facebook publish_actions permission during login in android I do

loginButton = (LoginButton) view.findViewById(R.id.login_button);
loginButton.setPublishPermissions(“publish_actions”);
loginButton.setUserInfoChangedCallback(new LoginButton.UserInfoChangedCallback() {
    @Override
    public void onUserInfoFetched(GraphUser user) {
        FacebookOptInFragment.this.user = user;
        updateUI();
    }
});

That’s all I need to do and I am done. User will first login and then get prompted to grant publishing permission. How do I do the exact same thing in iOS?

Note that I just now downloaded the Facebook SDK, which means I have the latest and greatest (in case that is relevant).