diff --git a/src/os/file.go b/src/os/file.go
index e717f171e72580330de5f8ced30de0a24edc331c..28231285542a19b8ffd6d545ffb5d460cc3c8fe1 100644
--- a/src/os/file.go
+++ b/src/os/file.go
@@ -109,7 +109,7 @@ func (e *LinkError) Unwrap() error {
 	return e.Err
 }
 
-// Read reads up to len(b) bytes from the File.
+// Read reads up to len(b) bytes from the File and stores them in b.
 // It returns the number of bytes read and any error encountered.
 // At end of file, Read returns 0, io.EOF.
 func (f *File) Read(b []byte) (n int, err error) {
@@ -166,7 +166,7 @@ type onlyWriter struct {
 	io.Writer
 }
 
-// Write writes len(b) bytes to the File.
+// Write writes len(b) bytes from b to the File.
 // It returns the number of bytes written and an error, if any.
 // Write returns a non-nil error when n != len(b).
 func (f *File) Write(b []byte) (n int, err error) {