/** Callback prototype for in progress transfers. The new_call_state is the state of the call resulting of the transfer, at the other party. */
typedef void (*LinphoneTransferStateChanged)(struct _LinphoneCore *lc, LinphoneCall *transfered, LinphoneCallState new_call_state);
/** Callback prototype */
-typedef void (*CallStatsUpdated)(struct _LinphoneCore *lc, LinphoneCall *call, LinphoneCallStats *stats);
+typedef void (*CallStatsUpdated)(struct _LinphoneCore *lc, LinphoneCall *call, const LinphoneCallStats *stats);
/**
* This structure holds all callbacks that the application should implement.