diff --git a/RtMidi.cpp b/RtMidi.cpp
index dd3f5792..221e2c85 100644
--- a/RtMidi.cpp
+++ b/RtMidi.cpp
@@ -654,15 +654,21 @@ double MidiInApi :: getMessage( std::vector<unsigned char> *message )
     return 0.0;
   }
 
+  RtMidiError::Type err = RtMidiError::NO_ERROR;
+  std::string err_msg;
   double timeStamp;
-  if ( !inputData_.queue.pop( message, &timeStamp ) )
+  if ( !inputData_.queue.pop( message, &timeStamp, &err, &err_msg ) )
     return 0.0;
 
+  if ( err != RtMidiError::NO_ERROR )
+    error( err, err_msg );
+
   return timeStamp;
 }
 
+// structure should be locked before using this method
 unsigned int MidiInApi::MidiQueue::size( unsigned int *__back,
-                                         unsigned int *__front )
+                                         unsigned int *__front)
 {
   // Access back/front members exactly once and make stack copies for
   // size calculation
@@ -676,6 +682,7 @@ unsigned int MidiInApi::MidiQueue::size( unsigned int *__back,
   // to member variables are needed.
   if ( __back ) *__back = _back;
   if ( __front ) *__front = _front;
+
   return _size;
 }
 
@@ -685,6 +692,8 @@ bool MidiInApi::MidiQueue::push( const MidiInApi::MidiMessage& msg )
   // Local stack copies of front/back
   unsigned int _back, _front, _size;
 
+  lock.lock();
+
   // Get back/front indexes exactly once and calculate current size
   _size = size( &_back, &_front );
 
@@ -692,29 +701,41 @@ bool MidiInApi::MidiQueue::push( const MidiInApi::MidiMessage& msg )
   {
     ring[_back] = msg;
     back = (back+1)%ringSize;
+    lock.unlock();
     return true;
   }
 
+  lock.unlock();
+
   return false;
 }
 
-bool MidiInApi::MidiQueue::pop( std::vector<unsigned char> *msg, double* timeStamp )
+bool MidiInApi::MidiQueue::pop( std::vector<unsigned char> *msg, double* timeStamp, RtMidiError::Type *err, std::string *err_msg )
 {
   // Local stack copies of front/back
   unsigned int _back, _front, _size;
 
+  lock.lock();
+
   // Get back/front indexes exactly once and calculate current size
   _size = size( &_back, &_front );
 
-  if ( _size == 0 )
+  if ( _size == 0 ) {
+    lock.unlock();
     return false;
+  }
 
   // Copy queued message to the vector pointer argument and then "pop" it.
   msg->assign( ring[_front].bytes.begin(), ring[_front].bytes.end() );
   *timeStamp = ring[_front].timeStamp;
+  *err = ring[_front].err;
+  *err_msg = ring[_front].err_msg;
 
   // Update front
   front = (front+1)%ringSize;
+
+  lock.unlock();
+
   return true;
 }
 
@@ -1658,6 +1679,17 @@ static void *alsaMidiHandler( void *ptr )
                 << (int) ev->data.connect.dest.port
                 << std::endl;
 #endif
+      if ( data->usingCallback ) {
+        std::cerr << "\nPort connection has closed!\n\n";
+        data->this_->error( RtMidiError::SYSTEM_ERROR, "Port connection has closed!" );
+      }
+      else {
+        MidiInApi::MidiMessage err_message;
+        err_message.err = RtMidiError::SYSTEM_ERROR;
+        err_message.err_msg = "Port connection has closed";
+        if ( !data->queue.push( err_message ) )
+          std::cerr << "\nMidiInCore: message queue limit reached!!\n\n";
+      }
       break;
 
     case SND_SEQ_EVENT_QFRAME: // MIDI time code
@@ -1840,6 +1872,7 @@ void MidiInAlsa :: initialize( const std::string& clientName )
   data->trigger_fds[1] = -1;
   apiData_ = (void *) data;
   inputData_.apiData = (void *) data;
+  inputData_.this_ = this;
 
   if ( pipe(data->trigger_fds) == -1 ) {
     errorString_ = "MidiInAlsa::initialize: error creating pipe objects.";
diff --git a/RtMidi.h b/RtMidi.h
index 4a38c8aa..952e7834 100644
--- a/RtMidi.h
+++ b/RtMidi.h
@@ -62,6 +62,7 @@
 
 #include <exception>
 #include <iostream>
+#include <mutex>
 #include <string>
 #include <vector>
 
@@ -81,6 +82,7 @@ class RTMIDI_DLL_PUBLIC RtMidiError : public std::exception
  public:
   //! Defined RtMidiError types.
   enum Type {
+    NO_ERROR = 0,
     WARNING,           /*!< A non-critical error. */
     DEBUG_WARNING,     /*!< A non-critical error which might be useful for debugging. */
     UNSPECIFIED,       /*!< The default, unspecified error type. */
@@ -555,9 +557,13 @@ class RTMIDI_DLL_PUBLIC MidiInApi : public MidiApi
     //! Time in seconds elapsed since the previous message
     double timeStamp;
 
+    // Can also contain an error (when bytes.size() == 0)
+    RtMidiError::Type err;
+    std::string err_msg;
+
     // Default constructor.
     MidiMessage()
-      : bytes(0), timeStamp(0.0) {}
+      : bytes(0), timeStamp(0.0), err(RtMidiError::NO_ERROR) {}
   };
 
   struct MidiQueue {
@@ -565,12 +571,13 @@ class RTMIDI_DLL_PUBLIC MidiInApi : public MidiApi
     unsigned int back;
     unsigned int ringSize;
     MidiMessage *ring;
+    std::mutex lock;
 
     // Default constructor.
     MidiQueue()
       : front(0), back(0), ringSize(0), ring(0) {}
     bool push( const MidiMessage& );
-    bool pop( std::vector<unsigned char>*, double* );
+    bool pop( std::vector<unsigned char>*, double*, RtMidiError::Type*, std::string* );
     unsigned int size( unsigned int *back=0, unsigned int *front=0 );
   };
 
@@ -587,6 +594,7 @@ class RTMIDI_DLL_PUBLIC MidiInApi : public MidiApi
     RtMidiIn::RtMidiCallback userCallback;
     void *userData;
     bool continueSysex;
+    MidiInApi *this_;
 
     // Default constructor.
     RtMidiInData()