On Sunday 20 July 2003 05:44, [EMAIL PROTECTED] wrote:
> I use kannel purely to receive sms messages using a siemens mc35 gsm
> modem. I spoke to someone about kannel and they said they used their own
> program instead of it because it didn't poll the modem fast enough.

How do you define "fast enough" ? please note that GSM modems are not very 
fast creatures, and at most they can receive a message every 4-5 seconds or 
so. also - polling is only meant as a last ditch effort to get a modem 
working even though it does not forward incoming messages to the TE 
regardless of configuration settings : it should not be used instead of 
properly configuring the modem to send notification directly to the TE.

> The fastest it can poll (using the keepalive) is 1 second. 

of course. the timeout calculations are based on the POSIX time() system call 
that has a resolution of 1 second. not that I think it'll be difficult to use 
some other kind of timing mechanism, like gettimeofday(), but IMO it won't 
matter any, as the response to any modem command is about 0.5 seconds, and if 
there are messages in the buffer they will have to be read and removed - 
which takes many more seconds. all in all, even 1 second polling interval is 
too fast IMHO, and setting it to about 20 seconds is the lowest value that 
actually makes sense. the default 60 seconds should be sufficient in most 
cases.
>
> I tried to work it out but I don't get the way it tests against
> time(NULL). Hopefully someone can help.

Not that difficult - it stores the last time it did the check in a local 
variable. each iteration it tests whether a new check should be run by adding 
the interval requested to the last time value and comparing it against the 
current time value.

All in all, if you are really interested in reception of messages faster then 
polling every second would allow, then I suggest you dispose of your GSM 
modem and look for another solution. also, please note again that the 
preferred method to receive incoming messages is through notifications sent 
by the modem. if your modem does not do that, check your CNMI settings 
against your modem's manual.

> To initialize the modem the first time I run kannel after a reboot I
> still have to load the at driver. Somehow this triggers something that
> at2 doesn't. Only need to do it once. 

This is a known issue - check the STATUS file for a simple workaround.

-- 
Oded Arbel
m-Wise mobile solutions
[EMAIL PROTECTED]

+972-9-9581711 (116)
+972-67-340014

::..
The evaluation of an action as 'practical' . . . depends on what it is that 
one wishes to practice.


Reply via email to