diff --git a/usr.bin/procstat/procstat.h b/usr.bin/procstat/procstat.h
--- a/usr.bin/procstat/procstat.h
+++ b/usr.bin/procstat/procstat.h
@@ -44,6 +44,7 @@
 	PS_OPT_SIGNUM		= 0x08,
 	PS_OPT_VERBOSE		= 0x10,
 	PS_MODE_COMPAT		= 0x20,
+	PS_MODE_NO_KINFO_PROC	= 0x40,
 };
 
 #define PS_SUBCOMMAND_OPTS			\
diff --git a/usr.bin/procstat/procstat.c b/usr.bin/procstat/procstat.c
--- a/usr.bin/procstat/procstat.c
+++ b/usr.bin/procstat/procstat.c
@@ -449,7 +449,8 @@
 	}
 
 	/* Must specify either the -a flag or a list of pids. */
-	if (!(aflag == 1 && argc == 0) && !(aflag == 0 && argc > 0))
+	if (!(aflag == 1 && argc == 0) && !(aflag == 0 && argc > 0) &&
+	    (cmd->cmp & PS_MODE_NO_KINFO_PROC) == 0)
 		usage(cmd);
 
 	if (memf != NULL)
@@ -465,6 +466,11 @@
 		xo_open_container(progname);
 		xo_open_container(xocontainer);
 
+		if ((cmd->cmp & PS_MODE_NO_KINFO_PROC) != 0) {
+			cmd->cmd(prstat, NULL);
+			goto iter;
+		}
+
 		if (aflag) {
 			p = procstat_getprocs(prstat, KERN_PROC_PROC, 0, &cnt);
 			if (p == NULL)
@@ -520,6 +526,7 @@
 			}
 		}
 
+iter:
 		xo_close_container(xocontainer);
 		xo_close_container(progname);
 		xo_finish();