The OMNeT⁠+⁠+ runtime has the ability to launch an external debugger and have it attached to the simulation process. One can configure a simulation to launch the debugger immediately on startup, or when an error (runtime error or crash) occurs. This just-in-time debugging facility was primarily intended for use on Linux.

To turn on just-in-time debugging, set the debugger-attach-on-startup or debugger-attach-on-error configuration option to true. You can do so by e.g. adding the appropriate line to omnetpp.ini, or specifying --debugger-attach-on-startup=true in the Additional arguments field in the launch configuration dialog. It is also possible to configure the debugger command line.