===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/environ.c,v
retrieving revision 1.19
retrieving revision 1.20
diff -u -r1.19 -r1.20
--- src/usr.bin/tmux/environ.c	2017/04/25 15:35:10	1.19
+++ src/usr.bin/tmux/environ.c	2017/05/11 07:34:54	1.20
@@ -1,4 +1,4 @@
-/* $OpenBSD: environ.c,v 1.19 2017/04/25 15:35:10 nicm Exp $ */
+/* $OpenBSD: environ.c,v 1.20 2017/05/11 07:34:54 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -208,16 +208,24 @@
 
 /* Log the environment. */
 void
-environ_log(struct environ *env, const char *prefix)
+environ_log(struct environ *env, const char *fmt, ...)
 {
 	struct environ_entry	*envent;
+	va_list			 ap;
+	char			*prefix;
 
+	va_start(ap, fmt);
+	vasprintf(&prefix, fmt, ap);
+	va_end(ap);
+
 	RB_FOREACH(envent, environ, env) {
 		if (envent->value != NULL && *envent->name != '\0') {
 			log_debug("%s%s=%s", prefix, envent->name,
 			    envent->value);
 		}
 	}
+
+	free(prefix);
 }
 
 /* Create initial environment for new child. */