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Wireshark-dev: Re: [Wireshark-dev] When is the preference variable updated?

From: Pascal Quantin <pascal.quantin@xxxxxxxxx>
Date: Thu, 12 Nov 2015 15:15:06 +0100


2015-11-12 15:07 GMT+01:00 Paul Offord <Paul.Offord@xxxxxxxxxxxx>:

Hi,

 

Frankly I feel a bit stupid asking this but I've been trying to figure it out for about 6 hours and I think I need help.  I have a dissector which I register like this:

 

static int tmsvc_port = 0;

 

void

proto_register_tmsvc(void)

{

    module_t *tmsvc_module;

 

    proto_tmsvc = proto_register_protocol("TM Syncro Service",

                                          "TmSyncro",

                                          "tmsvc");

 

    tmsvc_module = prefs_register_protocol(proto_tmsvc, NULL);

 

    prefs_register_uint_preference(tmsvc_module, "port",

                                   "TmSyncro service port",

                                   "When set to a value greater than 0 the TmSyncro service is started and accessible via the port number"

                                   10,

                                   &tmsvc_port);

 

}

 

Immediately after the prefs_register_uint_preference call I check the tmsvc_port value and its still 0 (and I've tried other initialisation values and they remain unchanged).  I was expecting tmsvc_port to be set to the value I last set by editing the preferences through the Wireshark menu system.

 

If I check with Menu -> Edit -> Preferences -> Protocols -> TmSyncro sure enough the value I last set is there.

 

When does my variable get updated?  Or alternatively, how can I retrieve the saved preference value?

 

Thanks and regards...Paul


Hi Paul,

the variable should be set according to the preference content when the  proto_reg_handoff_tmsvc function (that you register thanks to the prefs_register_protocol function) is called. Alternatively (if you do not need the reg_handoff function at all) the variable should be set when your dissector code is called.

Best regards,
Pascal.