-GSM_Error GSM_Initialise(char *model, char *device, char *initlength, GSM_ConnectionType connection, void (*rlp_handler)(RLP_F96Frame *frame), GSM_Statemachine *sm);
+extern GSM_Error GSM_Initialise(char *model, char *device, char *initlength, GSM_ConnectionType connection, void (*rlp_handler)(RLP_F96Frame *frame), GSM_Statemachine *sm);