diff --git a/include/unistd.h b/include/unistd.h
index 7e46f0e6971..835a6dffc47 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -571,6 +571,7 @@ int	 setloginclass(const char *);
 void	*setmode(const char *);
 int	 setpgrp(pid_t, pid_t);			/* obsoleted by setpgid() */
 void	 setproctitle(const char *_fmt, ...) __printf0like(1, 2);
+void	 setproctitle_fast(const char *_fmt, ...) __printf0like(1, 2);
 int	 setresgid(gid_t, gid_t, gid_t);
 int	 setresuid(uid_t, uid_t, uid_t);
 int	 setrgid(gid_t);