diff --git a/src/ioslaves/file/file.cpp b/src/ioslaves/file/file.cpp
--- a/src/ioslaves/file/file.cpp
+++ b/src/ioslaves/file/file.cpp
@@ -515,6 +515,11 @@
     // qDebug() << "File::open -- read";
     Q_ASSERT(mFile && mFile->isOpen());
 
+    if (bytes == 0) {
+        // Nothing to do...
+        return data(QByteArray());
+    }
+
     while (true) {
         QByteArray res = mFile->read(bytes);