diff --git a/dlls/winsock/socket.c b/dlls/winsock/socket.c
index 4ba80e52d0f..f606e72764e 100644
--- a/dlls/winsock/socket.c
+++ b/dlls/winsock/socket.c
@@ -1202,6 +1202,10 @@ INT WINAPI WINSOCK_ioctlsocket(SOCKET s, LONG cmd, ULONG *argp)
 		if( _get_sock_mask(s) )
 		{
 		    /* AsyncSelect()'ed sockets are always nonblocking */
+		    if (*argp) {
+			close(fd);
+			return 0;
+		    }
 		    SetLastError(WSAEINVAL); 
 		    close(fd);
 		    return SOCKET_ERROR;