// Written in the D programming language.

/**
 * Information about the target operating system, environment, and CPU.
 *
 * Macros:
 *      WIKI = Phobos/StdSystem
 *
 *  Copyright: Copyright Digital Mars 2000 - 2011
 *  License:   $(WEB www.boost.org/LICENSE_1_0.txt, Boost License 1.0).
 *  Authors:   $(WEB digitalmars.com, Walter Bright) and Jonathan M Davis
 *  Source:    $(PHOBOSSRC std/_system.d)
 */
module std.system;

immutable
{
    /++
        Operating system.

        Note:
            This is for cases where you need a value representing the OS at
            runtime. If you're doing something which should compile differently
            on different OSes, then please use $(D version(Win32)),
            $(D version(linux)), etc.

        See_Also:
            <a href="../version.html#PredefinedVersions">Predefined Versions</a>
      +/
    enum OS
    {
        win32 = 1, /// Microsoft 32 bit Windows systems
        linux,     /// All Linux Systems
        osx,       /// Mac OS X
        freeBSD,   /// FreeBSD
        solaris,   /// Solaris
        otherPosix /// Other Posix Systems
    }

    /// The OS that the program was compiled for.
    version(Win32)        OS os = OS.win32;
    else version(linux)   OS os = OS.linux;
    else version(OSX)     OS os = OS.osx;
    else version(FreeBSD) OS os = OS.freeBSD;
    else version(Posix)   OS os = OS.otherPosix;
    else static assert(0, "Unknown OS.");

    /++
        Byte order endianness.

        Note:
            This is intended for cases where you need to deal with endianness at
            runtime. If you're doing something which should compile differently
            depending on whether you're compiling on a big endian or little
            endian machine, then please use $(D version(BigEndian)) and
            $(D version(LittleEndian)).

        See_Also:
            <a href="../version.html#PredefinedVersions">Predefined Versions</a>
      +/
    enum Endian
    {
        bigEndian,   /// Big endian byte order
        littleEndian /// Little endian byte order
    }

    /// The endianness that the program was compiled for.
    version(LittleEndian) Endian endian = Endian.littleEndian;
    else                  Endian endian = Endian.bigEndian;
}

