diff -r 0535c03b2b9f src/jdk.attach/share/classes/sun/tools/attach/HotSpotVirtualMachine.java
--- a/src/jdk.attach/share/classes/sun/tools/attach/HotSpotVirtualMachine.java	Thu Sep 08 23:43:47 2016 -0400
+++ b/src/jdk.attach/share/classes/sun/tools/attach/HotSpotVirtualMachine.java	Fri Sep 09 22:12:57 2016 +0900
@@ -36,6 +36,8 @@
 import java.io.InputStreamReader;
 import java.util.Properties;
 import java.util.stream.Collectors;
+import java.util.regex.Pattern;
+import java.util.regex.Matcher;
 
 /*
  * The HotSpot implementation of com.sun.tools.attach.VirtualMachine.
@@ -57,18 +59,27 @@
     private void loadAgentLibrary(String agentLibrary, boolean isAbsolute, String options)
         throws AgentLoadException, AgentInitializationException, IOException
     {
-        InputStream in = execute("load",
-                                 agentLibrary,
-                                 isAbsolute ? "true" : "false",
-                                 options);
-        try {
-            int result = readInt(in);
-            if (result != 0) {
-                throw new AgentInitializationException("Agent_OnAttach failed", result);
+        try (BufferedReader reader = new BufferedReader(
+                   new InputStreamReader(
+                            execute("load", agentLibrary,
+                                     Boolean.toString(isAbsolute), options)))) {
+            String result = reader.readLine();
+            if (result == null) {
+                throw new AgentLoadException("Target VM did not respond");
+            } else {
+                Matcher matcher = Pattern.compile("^return code: (\\d+)$")
+                                         .matcher(result);
+                if (matcher.matches()) {
+                    int retCode = Integer.parseInt(matcher.group(1));
+                    if (retCode != 0) {
+                        throw new AgentInitializationException(
+                                              "Agent_OnAttach failed", retCode);
+                    }
+                } else {
+                    throw new AgentLoadException(result);
+                }
             }
-        } finally {
-            in.close();
-
         }
     }