asterisk users - Oct 2004 - Howtos on writting applications or modules ?

Hi,

I'm particularly interested in extending some of existing modules, like
cdr_csv for example. I've taken a closer look at the source and I see, that
it registers subroutine to get called to deal with CDR data.

I have following more general questions regarding app or modules API:
- where could I find more info on modules API ?
- what types of modules exist (like maybe modules that are called only on
certain events, then modules that are called in certain time intervals
etc...)
- what existing modules are good examples of different types to start at ?
- if I open tcp port in one module - can I use it in another module ?

Thanks in advance,

Robert.

> - where could I find more info on modules API ?
    There isn't really any hard core documentation, but I think you can run
'make progdocs' and get some stuff. Everything I've learned/needed
to learn
about the API I have learned from reading the code to other modules/apps.
> - what types of modules exist (like maybe modules that are called only on
> certain events, then modules that are called in certain time intervals
> etc...)
    Got no clue on that. Most of the modules/apps I've written/patched are
loaded by issuing 'load <mod name>.so" on the CLI. Most
modules/apps are
loaded and then something triggers asterisk to execute the main routine of
that module/app (the name of that routine is set when the mod/app is
registered).
> - what existing modules are good examples of different types to start at ?
    everything inside apps/
> - if I open tcp port in one module - can I use it in another module ?
    I don't believe you can share resources across modules like that. For
instance, if I have two seperate apps that both connect to database, I do
not believe (nor think it wise) to share a connection handler between them.

Matthew