Index: usr.bin/grep/grep.c
===================================================================
--- usr.bin/grep/grep.c
+++ usr.bin/grep/grep.c
@@ -728,7 +728,7 @@
 	if ((aargc == 0 || aargc == 1) && !Hflag)
 		hflag = true;
 
-	if (aargc == 0)
+	if (aargc == 0 && (dirbehave != DIR_RECURSE || patterns == 0))
 		exit(!procfile("-"));
 
 	if (dirbehave == DIR_RECURSE)
Index: usr.bin/grep/util.c
===================================================================
--- usr.bin/grep/util.c
+++ usr.bin/grep/util.c
@@ -111,6 +111,7 @@
 	FTSENT *p;
 	int c, fts_flags;
 	bool ok;
+	char **tdir = NULL;
 
 	c = fts_flags = 0;
 
@@ -128,7 +129,14 @@
 
 	fts_flags |= FTS_NOSTAT | FTS_NOCHDIR;
 
-	if (!(fts = fts_open(argv, fts_flags, NULL)))
+	if (argv[0] == NULL) {
+		tdir = grep_malloc(2 * sizeof(char *));
+		if((tdir[0] = getcwd(NULL, 0)) == NULL)
+			err(2, "getcwd");
+		tdir[1] = NULL;
+	}
+
+	if (!(fts = fts_open((tdir != NULL ? tdir : argv), fts_flags, NULL)))
 		err(2, "fts_open");
 	while ((p = fts_read(fts)) != NULL) {
 		switch (p->fts_info) {
@@ -165,6 +173,12 @@
 	}
 
 	fts_close(fts);
+
+	if (tdir != NULL) {
+			free(tdir[0]);
+			free(tdir);
+	}
+
 	return (c);
 }