diff --git a/src/thread/thread.h b/src/thread/thread.h
index 28c8b59988..ecfd655fb6 100644
--- a/src/thread/thread.h
+++ b/src/thread/thread.h
@@ -133,6 +133,11 @@ void SetSelfAsMainThread();
  */
 bool IsMainThread();
 
+/**
+ * @return true if the current thread definitely a "non-main" thread. If in doubt returns false.
+ */
+bool IsNonMainThread();
+
 /**
  * Get the name of the current thread, if any.
  * @param str The start of the buffer.
diff --git a/src/thread/thread_morphos.cpp b/src/thread/thread_morphos.cpp
index 322a2ab534..259b0a56b1 100644
--- a/src/thread/thread_morphos.cpp
+++ b/src/thread/thread_morphos.cpp
@@ -199,5 +199,6 @@ private:
 void SetSelfAsMainThread() { }
 
 bool IsMainThread() { return false; }
+bool IsNonMainThread() { return false; }
 
 int GetThreadName(char *str, const char *last) { return 0; }
diff --git a/src/thread/thread_none.cpp b/src/thread/thread_none.cpp
index 30f1adeb6a..175cf32015 100644
--- a/src/thread/thread_none.cpp
+++ b/src/thread/thread_none.cpp
@@ -37,5 +37,6 @@ public:
 void SetSelfAsMainThread() { }
 
 bool IsMainThread() { return true; }
+bool IsNonMainThread() { return false; }
 
 int GetThreadName(char *str, const char *last) { return 0; }
diff --git a/src/thread/thread_os2.cpp b/src/thread/thread_os2.cpp
index c666bbced7..41ae19ab38 100644
--- a/src/thread/thread_os2.cpp
+++ b/src/thread/thread_os2.cpp
@@ -150,4 +150,6 @@ void SetSelfAsMainThread() { }
 
 bool IsMainThread() { return false; }
 
+bool IsNonMainThread() { return false; }
+
 int GetThreadName(char *str, const char *last) { return 0; }
diff --git a/src/thread/thread_pthread.cpp b/src/thread/thread_pthread.cpp
index f00ae0bb8f..a6aeb521f4 100644
--- a/src/thread/thread_pthread.cpp
+++ b/src/thread/thread_pthread.cpp
@@ -203,6 +203,11 @@ bool IsMainThread()
 	return main_thread == pthread_self();
 }
 
+bool IsNonMainThread()
+{
+	return main_thread != pthread_self();
+}
+
 int GetThreadName(char *str, const char *last)
 {
 #if defined(__GLIBC__)
diff --git a/src/thread/thread_win32.cpp b/src/thread/thread_win32.cpp
index c7e13a775b..c7831040b0 100644
--- a/src/thread/thread_win32.cpp
+++ b/src/thread/thread_win32.cpp
@@ -185,6 +185,11 @@ bool IsMainThread()
 	return main_thread_id == GetCurrentThreadId();
 }
 
+bool IsNonMainThread()
+{
+	return main_thread_id != GetCurrentThreadId();
+}
+
 static std::map<uint, std::string> _thread_name_map;
 static ThreadMutex_Win32 _thread_name_map_mutex;