Allow strings(1) to operate on more than one file

strings.c

@@ -9,7 +9,7 @@ static void dostrings(FILE *fp, const char *fname);
 static void
 usage(void)
 {
-	eprintf("usage: %s file\n", argv0);
+	eprintf("usage: %s file...\n", argv0);
 }
 
 int
@@ -22,13 +22,15 @@ main(int argc, char *argv[])
 		usage();
 	} ARGEND;
 
-	if (argc > 0) {
-		if (!(fp = fopen(argv[0], "r")))
-			eprintf("open %s:", argv[0]);
-		dostrings(fp, argv[0]);
-		fclose(fp);
-	} else {
+	if (argc == 0) {
 		dostrings(stdin, "<stdin>");
+	} else {
+		for (; argc > 0; argc--, argv++) {
+			if (!(fp = fopen(argv[0], "r")))
+				eprintf("open %s:", argv[0]);
+			dostrings(fp, argv[0]);
+			fclose(fp);
+		}
 	}
 
 	return EXIT_SUCCESS;