Hi Friends, i'm using mod_nibblebill for billing on FS, i bundled event processing fucntions when status change, e.g. /* on_routing */ check_billing_before_routing, and * on_hangup */ process_hangup, as below, however, i found if i make a call containing two-legs e.g. user 1001 call user 1002, then the FS core dump. but if i only make one leg call, e.g. call 888 for IVR, then no problem occure, i found the problem within function "check_billing_before_routing" (because once i comment all of lines within this func, the core did not dump). below is the func "check_billing_before_routing", can anyone help advise what's wrong? how should i correct it, thanks. static switch_status_t check_billing_before_routing(switch_core_session_t *session) { //charles, check billing before routing the call char buf[128]; char cmd[100] = "check_billing_before_answer"; FILE *pp = NULL; const char* in_username = NULL; const char* in_calledstation = NULL; const char* in_uniqueid = NULL; const char* in_network_addr = NULL; const char* in_type = "9"; int is_b; //const char* full_cmd; int i_continue = 1; switch_channel_t *channel = NULL; in_uniqueid = switch_core_session_get_uuid(session); channel = switch_core_session_get_channel(session); /*only billing on a leg*/ is_b = channel && switch_channel_get_originator_caller_profile(channel); printf("is_b is: %d\n", is_b); if(is_b) { return SWITCH_STATUS_SUCCESS; } /* Lock this session's data for this module while we tinker with it */ if (globals.mutex) { switch_mutex_lock(globals.mutex); } in_username = switch_channel_get_variable(channel, "caller_id_number"); in_calledstation = switch_channel_get_variable(channel, "destination_number"); in_network_addr = switch_channel_get_variable(channel, "network_addr"); /* Done checking - release lock */ if (globals.mutex) { switch_mutex_unlock(globals.mutex); } switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "check_billing_before_routing, in_username: %s, in_calledstation: %s, in_uniqueid: %s in_type: %s, in_network_addr: %s \n", in_username, in_calledstation, in_uniqueid, in_type, in_network_addr); strcat(cmd, " "); strcat(cmd, in_username); strcat(cmd, " "); strcat(cmd, in_calledstation); strcat(cmd, " "); strcat(cmd, in_uniqueid); strcat(cmd, " "); strcat(cmd, in_type); strcat(cmd, " "); strcat(cmd, in_network_addr); printf("excute external cmd: "); printf(cmd); printf("\n"); if( (pp = popen(cmd, "r")) == NULL ) { printf("popen() error!\n"); exit(1); } while(fgets(buf, sizeof buf, pp)) { printf("the result of excuting external cmd: %s", buf); } if(pp) { pclose(pp); } i_continue = atoi(buf); printf("i_continue: %d", i_continue); if (!i_continue) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "call was not authorized to continue \n"); transfer_call(session, globals.nobal_action); } return SWITCH_STATUS_SUCCESS; } Core dump logs: freeswitch@freeswitch> 2011-10-24 16:30:26.583369 [NOTICE] mod_xml_rpc.c:969 Starting HTTP Port 8787, DocRoot [/usr/local/freeswitch/htdocs] 2011-10-24 16:30:29.454743 [WARNING] sofia_reg.c:1337 SIP auth challenge (INVITE) on sofia profile 'internal' for [6628@224.193.106.204] from ip 223.128.70.10 2011-10-24 16:30:30.254710 [NOTICE] switch_channel.c:897 New Channel sofia/internal/8068@224.193.106.204 [196a50b8-eaa0-4ef0-a674-18602117f5ec] is_b is: 0 excute external cmd: check_billing_before_answer 8068 6628 196a50b8-eaa0-4ef0-a674-18602117f5ec 9 223.128.70.10 2011-10-24 16:30:30.254710 [INFO] mod_nibblebill.c:1017 check_billing_before_routing, in_username: 8068, in_calledstation: 6628, in_uniqueid: 196a50b8-eaa0-4ef0-a674-18602117f5ec in_type: 9, in_network_addr: 223.128.70.10 the result of excuting external cmd: the result of excuting external cmd: 60 Segmentation fault (core dumped) [root@freeswitch bin]# -- Regards, Charles