Fix reading-files example to not show out-of-bounds bytes

Fixes #165

examples/reading-files/reading-files.go

@@ -40,7 +40,7 @@ func main() {
 	b1 := make([]byte, 5)
 	n1, err := f.Read(b1)
 	check(err)
-	fmt.Printf("%d bytes: %s\n", n1, string(b1))
+	fmt.Printf("%d bytes: %s\n", n1, string(b1[:n1]))
 
 	// You can also `Seek` to a known location in the file
 	// and `Read` from there.
@@ -49,7 +49,8 @@ func main() {
 	b2 := make([]byte, 2)
 	n2, err := f.Read(b2)
 	check(err)
-	fmt.Printf("%d bytes @ %d: %s\n", n2, o2, string(b2))
+	fmt.Printf("%d bytes @ %d: ", n2, o2)
+	fmt.Printf("%v\n", string(b2[:n2]))
 
 	// The `io` package provides some functions that may
 	// be helpful for file reading. For example, reads
@@ -80,5 +81,4 @@ func main() {
 	// be scheduled immediately after `Open`ing with
 	// `defer`).
 	f.Close()
-
 }

examples/reading-files/reading-files.hash

@@ -1,2 +1,2 @@
-2aa7a2e248065cebfa6f8eece3234b5ffa710273
-GQgp-I3dLb2
+463a6f2999a023887af6b23c8f79f24978eb8115
+cocJ6kBH_iZ

examples/reading-files/reading-files.sh

@@ -1,6 +1,6 @@
 $ echo "hello" > /tmp/dat
 $ echo "go" >>   /tmp/dat
-$ go run reading-files.go 
+$ go run reading-files.go
 hello
 go
 5 bytes: hello