--- a/ExternalStream.st	Tue Nov 22 12:37:33 2016 +0100
+++ b/ExternalStream.st	Tue Nov 22 19:19:39 2016 +0100
@@ -408,7 +408,7 @@
               if ((handleType == @symbol(socketFilePointer) && ((ok = ioctlsocket((SOCKET)_get_osfhandle(fileno(f)),FIONREAD,&res) == 0), 1)) \
                   || (handleType == @symbol(socketHandle) && ((ok = ioctlsocket((SOCKET)(f), FIONREAD, &res) == 0), 1)) \
                   || (handleType == @symbol(pipeFilePointer) && ((ok = PeekNamedPipe((HANDLE)_get_osfhandle(fileno(f)),0, 0,0,&res,0)), 1))) { \
-                  if (!ok) { (ret) = -1; break; }       \
+                  if (!ok) { (ret) = -1; CLEAR_ERRNO; break; }       \
                   if (res > 0) {                        \
                       if (res > ((cnt)-__offs))         \
                           res = (cnt)-__offs;           \
@@ -548,7 +548,7 @@
                 if ((handleType == @symbol(socketFilePointer) && ((ok = ioctlsocket((SOCKET)_get_osfhandle(fileno(f)),FIONREAD,&res) == 0), 1)) \
                     || (handleType == @symbol(socketHandle) && ((ok = ioctlsocket((SOCKET)(f), FIONREAD, &res) == 0), 1)) \
                     || (handleType == @symbol(pipeFilePointer) && ((ok = PeekNamedPipe((HANDLE)_get_osfhandle(fileno(f)),0, 0,0,&res,0)), 1))) { \
-                   if (!ok) { (ret) = -1; break; }  \
+                   if (!ok) { (ret) = -1; CLEAR_ERRNO; break; }       \
                    if (res > 0) {                   \
                         if (res > l) res = l;       \
                         READ((ret), f, __buf, res, handleType); \