diff --git a/xwords4/linux/linuxmain.c b/xwords4/linux/linuxmain.c
index 60b317c39..b823dfd6d 100644
--- a/xwords4/linux/linuxmain.c
+++ b/xwords4/linux/linuxmain.c
@@ -318,9 +318,10 @@ read_pipe_then_close( CommonGlobals* cGlobals, const TransportProcs* procs )
         /* 0-length packet closes it off */
         XP_LOGF( "%s: writing 0-length packet", __func__ );
         len = 0;
+#ifdef DEBUG
         ssize_t nwritten = write( fd, &len, sizeof(len) );
         XP_ASSERT( nwritten == sizeof(len) );
-
+#endif
         close( fd );
     }
 
diff --git a/xwords4/linux/xptypes.h b/xwords4/linux/xptypes.h
index 5aa150573..03baa755a 100644
--- a/xwords4/linux/xptypes.h
+++ b/xwords4/linux/xptypes.h
@@ -90,6 +90,7 @@ extern void linux_debugf(const char*, ...)
 #else
 
 # define XP_MALLOC(pool,nbytes)       malloc(nbytes)
+# define XP_CALLOC(pool,nbytes)       calloc(1,nbytes)
 # define XP_REALLOC(pool,p,s)         realloc((p),(s))
 # define XP_FREE(pool,p)              free(p)
 void linux_freep( void** ptrp );