$ ./signals ${platfdir}/small_platform.xml
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Turning off: Three callbacks should be triggered
> [0.000000] [s4u_test/INFO] First callback
> [0.000000] [s4u_test/INFO] Second callback
> [0.000000] [s4u_test/INFO] Third callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Disconnect the second callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Turning on: Two callbacks should be triggered
> [0.000000] [s4u_test/INFO] First callback
> [0.000000] [s4u_test/INFO] Third callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Disconnect the first callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Turning off: One callback should be triggered
> [0.000000] [s4u_test/INFO] Third callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Disconnect the third callback
> [Tremblay:worker:(1) 0.000000] [s4u_test/INFO] Turning on: No more callbacks