/n/sources/plan9/sys/src/cmd/usb/usbd/../lib/dev.c:482,493 - ../lib/dev.c:481,494
  int
  devctl(Dev *dev, char *fmt, ...)
  {
- 	char buf[128];
+ 	char *s;
+ 	int r;
  	va_list arg;
- 	char *e;
  
  	va_start(arg, fmt);
- 	e = vseprint(buf, buf+sizeof(buf), fmt, arg);
+ 	s = vsmprint(fmt, arg);
  	va_end(arg);
- 	return write(dev->cfd, buf, e-buf);
+ 	r = write(dev->cfd, s, strlen(s));
+ 	free(s);
+ 	return r;
  }