+/* unistd.h defines _POSIX_VERSION */
+# if !defined(OPENSSL_NO_SECURE_MEMORY) && defined(OPENSSL_SYS_UNIX) \
+ && ( (defined(_POSIX_VERSION) && _POSIX_VERSION >= 200112L) \
+ || defined(__sun) || defined(__hpux) || defined(__sgi) \
+ || defined(__osf__) )
+# define OPENSSL_SECURE_MEMORY /* secure memory is implemented */
+# endif