diff --git a/src/StreamEpics.cc b/src/StreamEpics.cc
index 7be2a73..12d7154 100644
--- a/src/StreamEpics.cc
+++ b/src/StreamEpics.cc
@@ -333,7 +333,6 @@ epicsExportAddress(drvet, stream);
 #ifdef EPICS_3_13
 void streamEpicsPrintTimestamp(char* buffer, size_t size)
 {
-    size_t tlen;
     char* c;
     TS_STAMP tm;
     tsLocalTime (&tm);
@@ -342,16 +341,17 @@ void streamEpicsPrintTimestamp(char* buffer, size_t size)
     if (c) {
         c[4] = 0;
     }
-    tlen = strlen(buffer);
-    sprintf(buffer+tlen, " %.*s", (int)(size-tlen-2), taskName(0));
+}
+
+static const char* epicsThreadGetNameSelf()
+{
+    return taskName(0);
 }
 #else // !EPICS_3_13
 void streamEpicsPrintTimestamp(char* buffer, size_t size)
 {
-    size_t tlen;
     epicsTime tm = epicsTime::getCurrent();
-    tlen = tm.strftime(buffer, size, "%Y/%m/%d %H:%M:%S.%06f");
-    sprintf(buffer+tlen, " %.*s", (int)(size-tlen-2), epicsThreadGetNameSelf());
+    tm.strftime(buffer, size, "%Y/%m/%d %H:%M:%S.%06f");
 }
 #endif // !EPICS_3_13
 
@@ -471,6 +471,7 @@ drvInit()
     debug("StreamProtocolParser::path = %s\n",
         StreamProtocolParser::path);
     StreamPrintTimestampFunction = streamEpicsPrintTimestamp;
+    StreamGetThreadNameFunction = epicsThreadGetNameSelf;
 
 #ifdef WITH_IOC_RUN
     initHookRegister(initHook);
diff --git a/src/StreamError.cc b/src/StreamError.cc
index ebcdd51..0836608 100644
--- a/src/StreamError.cc
+++ b/src/StreamError.cc
@@ -97,6 +97,7 @@ static void printTimestamp(char* buffer, size_t size)
 }
 
 void (*StreamPrintTimestampFunction)(char* buffer, size_t size) = printTimestamp;
+const char* (*StreamGetThreadNameFunction)(void) = NULL;
 
 void StreamError(const char* fmt, ...)
 {
@@ -116,13 +117,18 @@ void StreamError(int line, const char* file, const char* fmt, ...)
 
 void StreamVError(int line, const char* file, const char* fmt, va_list args)
 {
-    char timestamp[40];
     if (!(streamError || streamDebug)) return; // Error logging disabled
+    char timestamp[40];
+    const char *threadname = NULL;
     int timeStamped = streamMsgTimeStamped;
     if (timeStamped)
     {
         StreamPrintTimestampFunction(timestamp, sizeof(timestamp));
     }
+    if (StreamGetThreadNameFunction)
+    {
+        threadname = StreamGetThreadNameFunction();
+    }
 #ifdef va_copy
     if (StreamDebugFile)
     {
@@ -132,6 +138,10 @@ void StreamVError(int line, const char* file, const char* fmt, va_list args)
         {
             fprintf(StreamDebugFile, "%s ", timestamp);
         }
+        if (threadname)
+        {
+            fprintf(StreamDebugFile, "%s ", threadname);
+        }
         vfprintf(StreamDebugFile, fmt, args2);
         fflush(StreamDebugFile);
         va_end(args2);
@@ -142,6 +152,10 @@ void StreamVError(int line, const char* file, const char* fmt, va_list args)
     {
         fprintf(stderr, "%s ", timestamp);
     }
+    if (threadname)
+    {
+        fprintf(stderr, "%s ", threadname);
+    }
     if (file)
     {
         fprintf(stderr, "%s line %d: ", file, line);
@@ -164,6 +178,10 @@ print(const char* fmt, ...)
         StreamPrintTimestampFunction(timestamp, sizeof(timestamp));
         fprintf(fp, "%s ", timestamp);
     }
+    if (StreamGetThreadNameFunction)
+    {
+        fprintf(fp, "%s ", StreamGetThreadNameFunction());
+    }
     fprintf(fp, "%s:%d: ", f, line);
     vfprintf(fp, fmt, args);
     fflush(fp);
diff --git a/src/StreamError.h b/src/StreamError.h
index 1f4d544..ed0f9cb 100644
--- a/src/StreamError.h
+++ b/src/StreamError.h
@@ -35,6 +35,7 @@ extern int streamError;
 extern int streamDebugColored;
 extern int streamMsgTimeStamped;
 extern void (*StreamPrintTimestampFunction)(char* buffer, size_t size);
+extern const char* (*StreamGetThreadNameFunction)(void);
 
 void StreamError(int line, const char* file, const char* fmt, ...)
 __attribute__((__format__(__printf__,3,4)));