Reply To: List of post to edit in frontend

ok thanks, but to use template_redirect, how can I get the post_id to check if is_author o another rule? Because I can have the post_id of the page that contains the shortcode to update the post, but the post_id of the post to update is in the end of the url.

http://xxx.es/crear-articulo/?rwmb_frontend_field_post_id=540

?

Thanks.