+/******************************************************************************
+ * Detect operating systems. This probably needs completing.
+ * The result is that at least one OPENSSL_SYS_os macro should be defined.
+ * However, if none is defined, Unix is assumed.
+ **/
+
+#define OPENSSL_SYS_UNIX
+
+/* ----------------------- Macintosh, before MacOS X ----------------------- */
+#if defined(__MWERKS__) && defined(macintosh) || defined(OPENSSL_SYSNAME_MAC)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_MACINTOSH_CLASSIC
+#endif
+
+/* ----------------------- NetWare ----------------------------------------- */
+#if defined(NETWARE) || defined(OPENSSL_SYSNAME_NETWARE)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_NETWARE
+#endif
+
+/* ---------------------- Microsoft operating systems ---------------------- */
+
+/* Note that MSDOS actually denotes 32-bit environments running on top of
+ MS-DOS, such as DJGPP one. */
+#if defined(OPENSSL_SYSNAME_MSDOS)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_MSDOS
+#endif
+
+/* For 32 bit environment, there seems to be the CygWin environment and then
+ all the others that try to do the same thing Microsoft does... */
+#if defined(OPENSSL_SYSNAME_UWIN)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WIN32_UWIN
+#else
+# if defined(__CYGWIN32__) || defined(OPENSSL_SYSNAME_CYGWIN32)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WIN32_CYGWIN
+# else
+# if defined(_WIN32) || defined(OPENSSL_SYSNAME_WIN32)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WIN32
+# endif
+# if defined(OPENSSL_SYSNAME_WINNT)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WINNT
+# endif
+# if defined(OPENSSL_SYSNAME_WINCE)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WINCE
+# endif
+# endif
+#endif
+
+/* Anything that tries to look like Microsoft is "Windows" */
+#if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_WINNT) || defined(OPENSSL_SYS_WINCE)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_WINDOWS
+# ifndef OPENSSL_SYS_MSDOS
+# define OPENSSL_SYS_MSDOS
+# endif
+#endif
+
+/* DLL settings. This part is a bit tough, because it's up to the application
+ implementor how he or she will link the application, so it requires some
+ macro to be used. */
+#ifdef OPENSSL_SYS_WINDOWS
+# ifndef OPENSSL_OPT_WINDLL
+# if defined(_WINDLL) /* This is used when building OpenSSL to indicate that
+ DLL linkage should be used */
+# define OPENSSL_OPT_WINDLL
+# endif
+# endif
+#endif
+
+/* -------------------------------- OpenVMS -------------------------------- */
+#if defined(__VMS) || defined(VMS) || defined(OPENSSL_SYSNAME_VMS)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_VMS
+# if defined(__DECC)
+# define OPENSSL_SYS_VMS_DECC
+# elif defined(__DECCXX)
+# define OPENSSL_SYS_VMS_DECC
+# define OPENSSL_SYS_VMS_DECCXX
+# else
+# define OPENSSL_SYS_VMS_NODECC
+# endif
+#endif
+
+/* --------------------------------- OS/2 ---------------------------------- */
+#if defined(__EMX__) || defined(__OS2__)
+# undef OPENSSL_SYS_UNIX
+# define OPENSSL_SYS_OS2
+#endif
+
+/* --------------------------------- Unix ---------------------------------- */
+#ifdef OPENSSL_SYS_UNIX
+# if defined(linux) || defined(__linux__) || defined(OPENSSL_SYSNAME_LINUX)
+# define OPENSSL_SYS_LINUX
+# endif
+# ifdef OPENSSL_SYSNAME_MPE
+# define OPENSSL_SYS_MPE
+# endif
+# ifdef OPENSSL_SYSNAME_SNI
+# define OPENSSL_SYS_SNI
+# endif
+# ifdef OPENSSL_SYSNAME_ULTRASPARC
+# define OPENSSL_SYS_ULTRASPARC
+# endif
+# ifdef OPENSSL_SYSNAME_NEWS4
+# define OPENSSL_SYS_NEWS4
+# endif
+# ifdef OPENSSL_SYSNAME_MACOSX
+# define OPENSSL_SYS_MACOSX
+# endif
+# ifdef OPENSSL_SYSNAME_MACOSX_RHAPSODY
+# define OPENSSL_SYS_MACOSX_RHAPSODY
+# define OPENSSL_SYS_MACOSX
+# endif
+# ifdef OPENSSL_SYSNAME_SUNOS
+# define OPENSSL_SYS_SUNOS
+#endif
+# if defined(_CRAY) || defined(OPENSSL_SYSNAME_CRAY)
+# define OPENSSL_SYS_CRAY
+# endif
+# if defined(_AIX) || defined(OPENSSL_SYSNAME_AIX)
+# define OPENSSL_SYS_AIX
+# endif
+#endif
+
+/* --------------------------------- VOS ----------------------------------- */
+#if defined(__VOS__) || defined(OPENSSL_SYSNAME_VOS)
+# define OPENSSL_SYS_VOS
+#ifdef __HPPA__
+# define OPENSSL_SYS_VOS_HPPA
+#endif
+#ifdef __IA32__
+# define OPENSSL_SYS_VOS_IA32
+#endif
+#endif
+
+/* ------------------------------- VxWorks --------------------------------- */
+#ifdef OPENSSL_SYSNAME_VXWORKS
+# define OPENSSL_SYS_VXWORKS
+#endif
+
+/* --------------------------------- BeOS ---------------------------------- */
+#if defined(__BEOS__)
+# define OPENSSL_SYS_BEOS
+# include <sys/socket.h>
+# if defined(BONE_VERSION)
+# define OPENSSL_SYS_BEOS_BONE
+# else
+# define OPENSSL_SYS_BEOS_R5
+# endif
+#endif
+
+/**
+ * That's it for OS-specific stuff
+ *****************************************************************************/
+
+
+/* Specials for I/O an exit */
+#ifdef OPENSSL_SYS_MSDOS