+/**
+ * Make sure that the command has a prefix.
+ *
+ * If there is no prefix, send an error to the client and return from
+ * the function.
+ */
+#define _IRC_REQUIRE_PREFIX_OR_RETURN_(Client, Req) \
+if (!Req->prefix) { \
+ return IRC_WriteErrClient(Client, ERR_NEEDMOREPARAMS_MSG, \
+ Client_ID(Client), Req->command); \
+}
+