[asterisk-dev] Alarms on FXO channels

[Kevin P. Fleming]

Oron Peled wrote:

>    B. alarms_chan_zap.diff:
>       An alternative approach (and cleaner than A. in our opinion).
>       Since chan_zap already calls ZT_GET_PARAMS ioctl() immediately
>       after opening the channel, it knows about pending alarms
>       (asterisk >= 1.4.8) and should simply use this data.

I'm fine with this approach, but keep in mind that there aren't *any*
versions of Asterisk 1.4 that actually pay attention to channel alarms;
only Asterisk 1.6 and trunk do that. In Asterisk 1.4 we modified
chan_zap to suppress the pointless alarm/no alarm messages, but chan_zap
will still try to dial out FXO ports that are in red alarm.

>    Note: an advantage of A. is that it can provide a solution to old
>          asterisk versions (with the small price of unfriendly messages
>          as mentioned in 2.)

No, it won't. No 'old' versions of Asterisk pay attention to
channel-level alarms.
>    Note2: Oops, I just noticed we forgot to attach another handy
>           (but not essential) patch for zaptel.
>           This patch simply shows the channel alarms in /proc/zaptel/*
>           so it helps a lot to anybody that work with multiple FXO
>           channels (you can readily see which ones have battery,
>           regardless of current configuration).

This sounds like a useful patch, although the same information should
ideally be available in zttool as well.

-- 
Kevin P. Fleming
Director of Software Technologies
Digium, Inc. - "The Genuine Asterisk Experience" (TM)