I have been trying to get SPANDSP working for a number of days now with Asterisk 1.4. Last night I finally got it to compile, and somewhat work, however when I try to receive a fax, it immediately segfaults asterisk. Perhaps someone out there who knows more about coding, or the asterisk internals can tell me why, and fix it? Anyway, here’s the beginning of a SPANDSP / Asterisk 1.4 howto for you to get started. When I know how to fix the segfaulting issue, it will be posted here of course. See the howto after the jump.



Comment by Flewid on 2005-07-27 12:39:13 -0500

Hi Naftali,

Try out this link. I went through the configuration and documented it on the Wiki for everyone to see. If you haven’t tried voip-info.org yet, it’s where anything and everything voip is. Here is a direct link to the netweb page for these phones. Let me know if you have any more questions.


Comment by Frank on 2007-01-17 20:31:31 -0500


I managed compiling rxfax and txfax with asterisk 1.4.0 and current snapshot of spandsp.

But when I receive a Fax, rxfax is called in the dialplan but I can’t hear any sounds… or fax tones??

With old spandsp on asterisk 1.2.4 I could hear these fax tones when calling fax number with normal phone.

Did you find any solution to get rxfax to work with asterisk 1.4.0???

Thanks in advance

Comment by flewid on 2007-01-17 21:41:53 -0500

Hi Frank,

Thanks for the note. I have not yet been able to get it to work properly. I got it as far as you have, but it still seems to segfault. I’ve contacted steve underwood a number of times, as well as others on the mailing lists but he seems to not respond to us, so not too sure how the fixing is going.

I’ll update this article if I get it fixed. I’ve gone back to zap + regular fax machine for now sadly.


Comment by Remzi on 2007-02-14 11:58:52 -0500

I hit the same issue you are having, but in my case, txfax won’t even compile. I was using the files from snapshot folder (www.soft-switch.org/downloads/snapshots/spandsp/test-apps-asterisk-1.4/)

I have a thread at digium forums, if you are interested.


My error is:

[CC] app_rxtax.c -> app_txfax.o
gcc: cannot specify -o with -c or -S and multiple compilations
make[1]: *** [app_txfax.o] Error 1
make: *** [apps] Error 2

And like yourself, I am not a programmer, I can hack my way around though. Can you send me your current app_txfax.c and app_rxfax.c files, I’d like to take a look.

Comment by Flewid on 2007-02-14 15:59:20 -0500

Hi Remzi,

I still have not been able to get it functioning. I have heard some reports on the mailing list that others have gotten it half working. Generally the suggestion I am seeing is to simply to use hylafax plus the iaxfax solution. I did not want to do that, so I am waiting it out until someone successfully gets apprxfax and apptxfax working. Right now I am just using a regular fax machine attached to a zap channel to do my faxing. Feel free to send me an email flewid [at] flewid [dot] ca to discuss this more 🙂

Comment by Matt Gibson on 2007-03-04 00:11:33 -0500

Please check out my new posting if you are still struggling with getting this to work. Appears Asterisk 1.4.1 has fixed the issue and SpanDSP is now working again!

Updated Blog Article is in the Howto Section Entitled “Asterisk 1.4.1 and Spandsp – Working at last!”