#if defined(PIPE_SUBSYSTEM_WINDOWS_USER)
# include <winsock2.h>
# include <windows.h>
-#elif defined(PIPE_OS_LINUX) || defined(PIPE_OS_HAIKU) || defined(PIPE_OS_APPLE)
+#elif defined(PIPE_OS_LINUX) || defined(PIPE_OS_HAIKU) || defined(PIPE_OS_APPLE) || defined(PIPE_OS_CYGWIN)
# include <sys/socket.h>
# include <netinet/in.h>
# include <unistd.h>