Module development and code questions

how do I use hook_cron in a module? I just say blah_hook and throw in some code and it willl execute whenever the cron is run?

What's the deal w/ the location_views module?

The module is missing from the main modules page, and the download link is missing from the location_views module page. However, I did find the code in the CVS repository.

Hello

currently the text describing an event is unstructured.
How is it possible to force a user to fill in fileds of some kind of a form?
My idea is, that the text is stored as xml and fields with now value are not visibel execpt in edit mode.

Has somebody already worked on this subject?
And what to do to solve this problem?

Regards
Reiner

The readme.txt file for the Page_title module offers the actual syntax that needs to be executed in the PHPMyAdmin to add a new table to a database. But in other modules there is no help whatsoever in what to do. I have downloaded the Ping module but find no help at all in creating the tables in my database. Why is this?

I installed and enabled FlickerStickr module however when I try inserting photos I get the following error.

feof(): supplied argument is not a valid stream resource in /my/var/www/html/modules/flickrstickr/flickrstickr.module on line 33.

Any commnets appreciated.

I'm working on writing a simple module to authenticate users against an external source. I have a simple implementation of hook_auth working, but I'm trying to solve the following problem: When users are allowed to create account without administrator approval, everything works fine. However, if I try to create an account for them, my module seems to get bypassed.