--- /dev/null
+# Test whether O_CLOEXEC is defined.
+
+dnl Copyright 2017-2018 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_PREPROC_O_CLOEXEC],
+[
+ AC_CACHE_CHECK([for O_CLOEXEC],
+ [gl_cv_macro_O_CLOEXEC],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM([[#include <fcntl.h>
+ #ifndef O_CLOEXEC
+ choke me;
+ #endif
+ ]],
+ [[return O_CLOEXEC;]])],
+ [gl_cv_macro_O_CLOEXEC=yes],
+ [gl_cv_macro_O_CLOEXEC=no])])
+])