diff --git a/lib/downloader.cpp b/lib/downloader.cpp
index 9b68102e..02c478cc 100644
--- a/lib/downloader.cpp
+++ b/lib/downloader.cpp
@@ -183,7 +183,15 @@ namespace HTTP{
           return true; // Success!
         }
         // reset the data timeout
-        reqTime = Util::bootSecs();
+        if (reqTime != Util::bootSecs()){
+          if (progressCallback != 0){
+            if (!progressCallback()){
+              WARN_MSG("Download aborted by callback");
+              return false;
+            }
+          }
+          reqTime = Util::bootSecs();
+        }
       }
       if (getSocket()){
         FAIL_MSG("Timeout while retrieving %s (%zu/%" PRIu32 ")", link.getUrl().c_str(),
@@ -239,7 +247,15 @@ namespace HTTP{
           return true; // Success!
         }
         // reset the data timeout
-        reqTime = Util::bootSecs();
+        if (reqTime != Util::bootSecs()){
+          if (progressCallback != 0){
+            if (!progressCallback()){
+              WARN_MSG("Download aborted by callback");
+              return false;
+            }
+          }
+          reqTime = Util::bootSecs();
+        }
       }
       if (getSocket()){
         FAIL_MSG("Timeout while retrieving %s", link.getUrl().c_str());
diff --git a/lib/http_parser.cpp b/lib/http_parser.cpp
index 5265a283..391cfe19 100644
--- a/lib/http_parser.cpp
+++ b/lib/http_parser.cpp
@@ -786,6 +786,13 @@ bool HTTP::Parser::Read(std::string &strbuf){
   return parse(strbuf);
 }// HTTPReader::Read
 
+/// Checks download completion percentage.
+/// Returns zero if that doesn't make sense at the time or cannot be determined.
+uint8_t HTTP::Parser::getPercentage() const{
+  if (!seenHeaders || length < 1){return 0;}
+  return ((body.length() * 100) / length);
+}
+
 /// Attempt to read a whole HTTP response or request from a data buffer.
 /// If succesful, fills its own fields with the proper data and removes the response/request
 /// from the data buffer.
diff --git a/lib/http_parser.h b/lib/http_parser.h
index 8880690b..9172eae6 100644
--- a/lib/http_parser.h
+++ b/lib/http_parser.h
@@ -24,6 +24,7 @@ namespace HTTP{
     const std::string &GetHeader(const std::string &i) const;
     bool hasHeader(const std::string &i) const;
     void clearHeader(const std::string &i);
+    uint8_t getPercentage() const;
     const std::string &GetVar(const std::string &i) const;
     std::string getUrl();
     std::string allVars();
diff --git a/lib/procs.h b/lib/procs.h
index c0f7bb7f..e7edb4d0 100644
--- a/lib/procs.h
+++ b/lib/procs.h
@@ -20,7 +20,6 @@ namespace Util {
       static bool thread_handler;///< True while thread handler should be running.
       static void childsig_handler(int signum);
       static void exit_handler();
-      static void runCmd(std::string & cmd);
       static char* const* dequeToArgv(std::deque<std::string> & argDeq);
       static void grim_reaper(void * n);
     public:
diff --git a/lib/socket.cpp b/lib/socket.cpp
index 1a62cf85..4ab377fe 100644
--- a/lib/socket.cpp
+++ b/lib/socket.cpp
@@ -1272,7 +1272,9 @@ Socket::Connection Socket::Server::accept(bool nonblock){
   // we could do this through accept4 with a flag, but that call is non-standard...
   if (r < 0){
     if ((errno != EWOULDBLOCK) && (errno != EAGAIN) && (errno != EINTR)){
-      FAIL_MSG("Error during accept: %s. Closing server socket %d.", strerror(errno), sock);
+      if (errno != EINVAL){
+        FAIL_MSG("Error during accept: %s. Closing server socket %d.", strerror(errno), sock);
+      }
       close();
     }
     return Socket::Connection();
diff --git a/src/controller/controller_capabilities.cpp b/src/controller/controller_capabilities.cpp
index 6bd952dd..83b9a75c 100644
--- a/src/controller/controller_capabilities.cpp
+++ b/src/controller/controller_capabilities.cpp
@@ -184,17 +184,25 @@ namespace Controller {
       if ((*it).substr(0, 7) == "MistOut"){
         arg_one = Util::getMyPath() + (*it);
         conn_args[0] = arg_one.c_str();
-        capabilities["connectors"][(*it).substr(7)] = JSON::fromString(Util::Procs::getOutputOf((char**)conn_args));
-        if (capabilities["connectors"][(*it).substr(7)].size() < 1){
-          capabilities["connectors"].removeMember((*it).substr(7));
+        std::string entryName = (*it).substr(7);
+        capabilities["connectors"][entryName] = JSON::fromString(Util::Procs::getOutputOf((char**)conn_args));
+        if (capabilities["connectors"][entryName].size() < 1){
+          capabilities["connectors"].removeMember(entryName);
+        }else if (capabilities["connectors"][entryName]["version"].asStringRef() != PACKAGE_VERSION){
+          WARN_MSG("Output %s version mismatch (%s != " PACKAGE_VERSION ")", entryName.c_str(), capabilities["connectors"][entryName]["version"].asStringRef().c_str());
+          capabilities["connectors"].removeMember(entryName);
         }
       }
       if ((*it).substr(0, 6) == "MistIn" && (*it) != "MistInfo"){
         arg_one = Util::getMyPath() + (*it);
         conn_args[0] = arg_one.c_str();
-        capabilities["inputs"][(*it).substr(6)] = JSON::fromString(Util::Procs::getOutputOf((char**)conn_args));
-        if (capabilities["inputs"][(*it).substr(6)].size() < 1){
+        std::string entryName = (*it).substr(6);
+        capabilities["inputs"][entryName] = JSON::fromString(Util::Procs::getOutputOf((char**)conn_args));
+        if (capabilities["inputs"][entryName].size() < 1){
           capabilities["inputs"].removeMember((*it).substr(6));
+        }else if (capabilities["inputs"][entryName]["version"].asStringRef() != PACKAGE_VERSION){
+          WARN_MSG("Input %s version mismatch (%s != " PACKAGE_VERSION ")", entryName.c_str(), capabilities["inputs"][entryName]["version"].asStringRef().c_str());
+          capabilities["inputs"].removeMember(entryName);
         }
       }
     }
diff --git a/src/input/input.cpp b/src/input/input.cpp
index 14b77ed2..81407f4d 100644
--- a/src/input/input.cpp
+++ b/src/input/input.cpp
@@ -220,6 +220,7 @@ namespace Mist {
     Util::Config::streamName = streamName;
    
     if (config->getBool("json")) {
+      capa["version"] = PACKAGE_VERSION;
       std::cout << capa.toString() << std::endl;
       return 0;
     }
diff --git a/src/output/mist_out.cpp b/src/output/mist_out.cpp
index b5d02796..a0432cce 100644
--- a/src/output/mist_out.cpp
+++ b/src/output/mist_out.cpp
@@ -15,6 +15,7 @@ int main(int argc, char * argv[]) {
   mistOut::init(&conf);
   if (conf.parseArgs(argc, argv)) {
     if (conf.getBool("json")) {
+      mistOut::capa["version"] = PACKAGE_VERSION;
       std::cout << mistOut::capa.toString() << std::endl;
       return -1;
     }