--- IO-AIO/configure	2019/04/03 03:03:53	1.31
+++ IO-AIO/configure	2019/09/06 22:03:09	1.32
@@ -4827,6 +4827,38 @@
 $as_echo "#define HAVE_STATX 1" >>confdefs.h
 
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for accept4" >&5
+$as_echo_n "checking for accept4... " >&6; }
+if ${ac_cv_accept4+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+int main (void)
+{
+   int res;
+   res = accept4 (1, (struct sockaddr *)0, (socklen_t)0, SOCK_NONBLOCK | SOCK_CLOEXEC);
+   return 0;
+}
+
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_accept4=yes
+else
+  ac_cv_accept4=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_accept4" >&5
+$as_echo "$ac_cv_accept4" >&6; }
+test $ac_cv_accept4 = yes &&
+$as_echo "#define HAVE_ACCEPT4 1" >>confdefs.h
+
+
 cat >confcache <<\_ACEOF
 # This file is a shell script that caches the results of configure
 # tests run on this system so they can be shared between configure