Debugging

How to debug Telepathy problems.

Connection managers

Many Telepathy problems are not directly the fault of the user interface (such as Empathy), but of the connection managers (Gabble, Idle, Salut, Haze, Butterfly, Telepathy-SofiaSIP, ...), which are the services responsible for actually connecting to your IM accounts. CMs generally run in the background, with no visible output; in order to get debugging output from them, you'll need to run them manually.

Connection manager executables don't generally live in your $PATH, so you'll need to provide the full path in the following commands (rather than just telepathy-foo) to invoke them.

Obtaining logs

First, quit your IM client (such as Empathy), and wait a few seconds for the connection managers to quit of their own accord. Then, in a terminal, run: 

FOO_PERSIST=1 FOO_DEBUG=all /path/to/telepathy-foo 2>&1 | tee foo.log

(where foo should be gabble for Jabber, and the name of the relevant CM for the protocol you're having trouble with, as listed on Components). Now, start your IM client again, and reproduce the problem; debugging output should appear in your terminal, and be written to foo.log. (You can set the _DEBUG variable to values other than all if you only want the debugging output from a certain part of the CM, but usually this is unnecessary.)

If the connection manager complains about "name already or use" and quits immediately, you should kill any existing instances of it and try again.

Gabble

When debugging Gabble, it's usually a good idea to set LM_DEBUG=net so that the XML stanzas are also captured in the logfile.

Mission Control 5

Until Bug #22705 is fixed, it is necessary to set MC_DEBUG=1 to get Mission Control to output debug messages.

Debugging crashes

General

If you are experiencing crashes, it's a good idea to install any Telepathy debug packages provided by your distribution.

On Debian-like systems, debugging packages include:

GDB

You might be able to obtain debug information using gdb (for connection managers, you probably also want to use the X_PERSIST variable for this): 

$ GABBLE_PERSIST=1 gdb telepathy-gabble
GNU gdb 6.7.1-debian
Copyright (C) 2007 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i486-linux-gnu"...
Using host libthread_db library "/lib/i686/cmov/libthread_db.so.1".
(gdb) r
Starting program: /usr/bin/telepathy-gabble 
** (telepathy-gabble:17666): DEBUG: started version 0.6.0 (telepathy-glib version 0.7.0)

If the program crashes while running under gdb, use the "bt" command to obtain a backtrace.

Valgrind

Valgrind can find many bugs.

Electric Fence

Electric Fence can find some memory allocation bugs.

To use it, run Programs with LD_PRELOAD=/usr/lib/libefence.so.0.0.