Hi folks, I'm trying to get to the bottom of this bug: https://bugs.launchpad.net/ubuntu/+source/synaptiks/+bug/1039261 The tl;dr version is that the Python interpreter is somehow emitting two calls to the Xorg libXi function XIQueryVersion(), the first call sends a client XInput version number of 2.1 and then the second one sends 2.0 (seen using xtrace). The second call causes a BadValue error, because you're not meant to send a lower value on any later calls. This causes the comical error: # The version of the XInput extension installed on your system is # too old. Version 2.0 was found, but at least version 2.0 is required The problem is that the Python code only has the second call sending the 2.0 version number, there is no other call in the package that will send anything else, let alone the 2.1 value. So I want to generate a call trace every time the XIQueryVersion() function is called, but I'm struggling to get it to work. The killer at the moment is that both ltrace and gdb (when told to trace children) hang when python runs dash to run ldconfig which calls ldconfig.real and that blocks - so I never get to the point where the function gets called the first time. Any ideas? cheers, Chris -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC