Like in all other log.c file just use exit(1) in fatal() calls. This log.c should be further synced with the other log.c files.

usr.sbin/ripd/log.c

···
-/*	$OpenBSD: log.c,v 1.7 2017/03/21 12:06:56 bluhm Exp $ */
+/*	$OpenBSD: log.c,v 1.8 2021/01/19 10:16:44 claudio Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <[e-mail]>
···
 			logit(LOG_CRIT, "fatal in %s: %s",
 			    log_procname, emsg);
 
-	if (ripd_process == PROC_MAIN)
-		exit(1);
-	else				/* parent copes via SIGCHLD */
-		_exit(1);
+	exit(1);
 }
 
 void