diff --git a/conversions.go b/conversions.go
index a180884..876e134 100644
--- a/conversions.go
+++ b/conversions.go
@@ -401,8 +401,8 @@ func convertInMessage(
 
 	default:
 		o = &unknownOp{
-			opCode: inMsg.Header().Opcode,
-			inode:  fuseops.InodeID(inMsg.Header().Nodeid),
+			OpCode: inMsg.Header().Opcode,
+			Inode:  fuseops.InodeID(inMsg.Header().Nodeid),
 		}
 	}
 
diff --git a/debug.go b/debug.go
index 2003fc0..14e1d36 100644
--- a/debug.go
+++ b/debug.go
@@ -50,6 +50,9 @@ func describeRequest(op interface{}) (s string) {
 	case *interruptOp:
 		addComponent("fuseid 0x%08x", typed.FuseID)
 
+	case *unknownOp:
+		addComponent("opcode %d", typed.OpCode)
+
 	case *fuseops.ReadFileOp:
 		addComponent("handle %d", typed.Handle)
 		addComponent("offset %d", typed.Offset)
diff --git a/ops.go b/ops.go
index 8f52850..fd9bc26 100644
--- a/ops.go
+++ b/ops.go
@@ -22,8 +22,8 @@ import (
 // A sentinel used for unknown ops. The user is expected to respond with a
 // non-nil error.
 type unknownOp struct {
-	opCode uint32
-	inode  fuseops.InodeID
+	OpCode uint32
+	Inode  fuseops.InodeID
 }
 
 // Required in order to mount on OS X.