add_action ('init' finally worked with the first function! So thanks a million man.
anyway, problem: if I use 'init' the first function makes no distinction between publishing or editing. I wanted this function to happen only when the post is published.
But I guess this could be worked out by checking on other $_POST values such as 'publish' or 'post_status'.
Yet, for the sake of exploring possibilities, the second function should be better for my case....
Making use of
$id (I forgot to put
$id in the example here like you noted but it was present in my code when I tested it) it could alter the title after
$_POST and therefore be hooked into other actions other than 'init'. My experiments:
it does not work with
'save_post' seem to work but it causes Apache to crash down!
'wp_insert_post' creates a infinite series of empty posts titled 'test' until apache breaks down.
'edit_post' duplicates the post you're editing ad libitum until apache breaks down!!
I guess I'll work with the first... :)