diff --git a/xwords4/common/comms.c b/xwords4/common/comms.c
index acd55b5bf..357c3f69b 100644
--- a/xwords4/common/comms.c
+++ b/xwords4/common/comms.c
@@ -749,7 +749,7 @@ comms_setAddr( CommsCtxt* comms, const CommsAddrRec* addr )
 
 #ifdef XWFEATURE_RELAY
 XP_Bool
-comms_getRelayID( const CommsCtxt* comms, XP_U8* buf, XP_U16* lenp )
+comms_getRelayID( const CommsCtxt* comms, XP_UCHAR* buf, XP_U16* lenp )
 {
     XP_Bool success = comms->r.connName[0] != 0;
     if ( success ) {
diff --git a/xwords4/common/comms.h b/xwords4/common/comms.h
index c53a98fc7..03c52f866 100644
--- a/xwords4/common/comms.h
+++ b/xwords4/common/comms.h
@@ -165,7 +165,7 @@ void comms_getAddr( const CommsCtxt* comms, CommsAddrRec* addr );
 void comms_setAddr( CommsCtxt* comms, const CommsAddrRec* addr );
 
 #ifdef XWFEATURE_RELAY
-XP_Bool comms_getRelayID( const CommsCtxt* comms, XP_U8* buf, XP_U16* len );
+XP_Bool comms_getRelayID( const CommsCtxt* comms, XP_UCHAR* buf, XP_U16* len );
 #endif
 
 CommsConnType comms_getConType( const CommsCtxt* comms );