fs: fix ReadStream fails to read from existing fd

A ReadStream constructed from an existing file descriptor failed to start
reading automatically. Avoids a userspace call to ReadStream.prototype._read().

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/fs.js b/lib/fs.js
index 7b61c8984..3603232ab 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -1050,6 +1050,7 @@ var ReadStream = fs.ReadStream = function(path, options) {
   }
 
   if (this.fd !== null) {
+    this._read();
     return;
   }