[Freeswitch-users] How to identify the first REGISTERATION and do sth.

Dear friends, i would to excute an script after the 200 OK agaist teh first REGISTERATION from the user, so i need identify which one is the first REGISTERATION message, in the sofia_reg.c, i found below lines, however, it looks no help, could anyone can help advise, thanks. "if (sofia_test_pflag(profile, PFLAG_MESSAGE_QUERY_ON_REGISTER) || (reg_count == 1 && sofia_test_pflag(profile, PFLAG_MESSAGE_QUERY_ON_FIRST_REGISTER)))" -- Regards, Charles