Index: Modules/posixmodule.c
--- Modules/posixmodule.c.orig
+++ Modules/posixmodule.c
@@ -9223,7 +9223,7 @@ os_closerange_impl(PyObject *module, int fd_low, int f
     fdwalk(_fdwalk_close_func, lohi);
 #else
     fd_low = Py_MAX(fd_low, 0);
-#ifdef __FreeBSD__
+#if defined(__FreeBSD__) || defined(__OpenBSD__)
     if (fd_high >= sysconf(_SC_OPEN_MAX)) {
         /* Any errors encountered while closing file descriptors are ignored */
         closefrom(fd_low);