only support stdin for input

odl.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"bufio"
-	"flag"
 	"fmt"
 	"io"
 	"log"
@@ -14,20 +13,7 @@ import (
 )
 
 func main() {
-	flag.Parse()
+	Download(Read(".", os.Stdin))
-
-	var err error
-	f := os.Stdin
-	filename := flag.Arg(0)
-
-	if filename != "-" && filename != "" {
-		f, err = os.Open(filename)
-		if err != nil {
-			log.Fatalf("failed to open file %s: %v", filename, err)
-		}
-	}
-
-	Download(Read(".", f))
 }
 
 type request struct {