-/* e_os.h includes unistd.h, which 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 IMPLEMENTED
+/* e_os.h defines OPENSSL_SECURE_MEMORY if secure memory can be implemented */
+#ifdef OPENSSL_SECURE_MEMORY