don't try to preserve termios sans terminal

src/lib/termdesc.c

@@ -186,10 +186,12 @@ int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
                          unsigned noaltscreen, unsigned nocbreak){
   memset(ti, 0, sizeof(*ti));
   ti->utf8 = utf8;
+  if(fd >= 0){
     if(tcgetattr(fd, &ti->tpreserved)){
       fprintf(stderr, "Couldn't preserve terminal state for %d (%s)\n", fd, strerror(errno));
       return -1;
     }
+  }
   if(ncinputlayer_init(&ti->input, stdin)){
     return -1;
   }