diff --git a/README b/README
index 7915370..e21dd35 100644
--- a/README
+++ b/README
@@ -77,7 +77,7 @@ The following tools are implemented ('*' == finished, '#' == UTF-8 support,
 =*| test            yes                          none
 =*| time            yes                          none
 =*| touch           yes                          none
-#*  tr              yes                          none
+#*| tr              yes                          none
 =*| true            yes                          none
 =*| tty             yes                          none
 =*| uname           yes                          none
diff --git a/tr.c b/tr.c
index 6ca1488..3d067bc 100644
--- a/tr.c
+++ b/tr.c
@@ -192,7 +192,7 @@ main(int argc, char *argv[])
 		usage();
 	} ARGEND;
 
-	if (argc < 1 || argc > 2 || (argc == 1 && dflag == sflag))
+	if (!argc || argc > 2 || (argc == 1 && dflag == sflag))
 		usage();
 	set1ranges = makeset(argv[0], &set1, &set1check);
 	if (argc == 2)