Updated 2016-03-15 14:38:56 by bll

The ::tcl_platform global array (documented on the tclvars manpage) holds useful data concerning the platform on which a specific Tcl interpreter is running. This page is intended to list the values of tcl_platform on various systems. This might be useful for folks who are trying to adapt their code to different platforms.

The meaning of the element names are:

  • byteOrder - is the most significant, or least significant, byte first
  • machine - some info specific to the kind of hardware
  • os - a string identifying the operating system
  • osVersion - the version of the os
  • pathSeparator — character used to split variables like env(PATH) into a proper Tcl list (from 8.6)
  • platform - which of the major types of computers (or operating systems) is this?
  • pointerSize - bytes taken up by a void pointer (from 8.5)
  • user - user's login id
  • wordSize - number of bytes for a machine-word (actually, a long)
  • engine - script engine implementation (e.g. "Eagle", "TH1", "Jim", "Picol", "JTcl", "Tcl" 8.5.19+ / 8.6.5+, "Jacl", etc). See TIP #440.

Optionally present members include:

  • threaded - tcl configured with --enable-threads
  • debug - a windows tcl configured with --enable-debug

Eagle may provide the following members (other implementations may support some of these as well):

  • characterSize - number of bytes used to represent a single character. may be a range in the form of (lower-upper).
  • dirSeparator - character used to separate parts of a fully qualified file name.
  • host - name of the machine evaluating the script.
  • osPatchLevel - patch level of the operating system.
  • osServicePack - string identifying the service pack of the operating system.
  • patchLevel - patch level of Tcl implemented by the script engine.
  • processBits - number of address space bits for the process.
  • processors - number of logical processors for the process.
  • unicode - if present, characters are encoded using UCS2/UTF-16 or UCS4/UTF-32.
  • version - version of Tcl implemented by the script engine.

Is anyone aware of any other members?

LV In Tcl 8.5, a new platform package makes available new commands such as platform::generic and platform::identify .

LV How much of this information is generated dynamically, and how much of it really is generated statically at compile time?

  • byteOrder, wordSize, and pointerSize are dynamically generated.
    • DKF: These are architectural constants, i.e., are effectively static because sizeof(void*) yields a constant.
  • The statement which adds the threaded element is statically compiled into the system.
  • The platform entry is generated statically.
  • The os, and osVersion entries appear to be generated dynamically.
  • The machine entry is generated dynamically.
  • The user entry is generated dynamically (based on USER and LOGNAME environment variables)
  • The debug entry is statically added.

Examples from Different Systems edit

Please add the output of
  parray tcl_platform

here for your platform if it is not represented.

  AIX

AIX 4.3

tcl_platform(byteOrder) = bigEndian
tcl_platform(machine) = 003C87964C00
tcl_platform(os) = AIX
tcl_platform(osVersion) = 4.3
tcl_platform(platform) = unix

AIX 5.1 on PPC

tcl_platform(byteOrder) = bigEndian
tcl_platform(machine) = 0042065B4C00
tcl_platform(os) = AIX
tcl_platform(osVersion) = 5.1
tcl_platform(platform) = unix
tcl_platform(wordSize) = 4

AIX 6.1 on pSeries

tcl_platform(byteOrder) = bigEndian
tcl_platform(machine) = 000BF680D600
tcl_platform(os) = AIX
tcl_platform(osVersion) = 6.1
tcl_platform(platform) = unix
tcl_platform(wordSize) = 4

  Android

Android 4.2.2 "Jelly Bean"

  tcl_platform(byteOrder)     = littleEndian
  tcl_platform(machine)       = armv7l
  tcl_platform(os)            = Linux
  tcl_platform(osVersion)     = 3.0.36+
  tcl_platform(pathSeparator) = :
  tcl_platform(platform)      = unix
  tcl_platform(pointerSize)   = 4
  tcl_platform(threaded)      = 1
  tcl_platform(user)          = u0_a71
  tcl_platform(wordSize)      = 4

Android 4.4.2 "KitKat"

  tcl_platform(byteOrder)     = littleEndian
  tcl_platform(machine)       = armv7l
  tcl_platform(os)            = Linux
  tcl_platform(osVersion)     = 3.4.0
  tcl_platform(pathSeparator) = :
  tcl_platform(platform)      = unix
  tcl_platform(pointerSize)   = 4
  tcl_platform(threaded)      = 1
  tcl_platform(user)          = u0_a107
  tcl_platform(wordSize)      = 4

Android 5.0.2 "Lollipop"

  tcl_platform(byteOrder)     = littleEndian
  tcl_platform(machine)       = armv7l
  tcl_platform(os)            = Linux
  tcl_platform(osVersion)     = 3.4.0-perf-g5fe8ba4
  tcl_platform(pathSeparator) = :
  tcl_platform(platform)      = unix
  tcl_platform(pointerSize)   = 4
  tcl_platform(threaded)      = 1
  tcl_platform(user)          = u0_a3
  tcl_platform(wordSize)      = 4

User names are assigned automatically by the OS.

  HP-UX

HP-UX 10.20

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = 9000/715
 tcl_platform(os)        = HP-UX
 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = x86_64
 tcl_platform(os)            = Darwin
 tcl_platform(osVersion)     = 14.3.0
 tcl_platform(pathSeparator) = :
 tcl_platform(platform)      = unix
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(user)          = bll
 tcl_platform(wordSize)      = 8
 tcl_platform(osVersion) = B.10.20
 tcl_platform(platform)  = unix

HP-UX 11

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = 9000/782
 tcl_platform(os)        = HP-UX
 tcl_platform(osVersion) = B.11.00
 tcl_platform(platform)  = unix

HP-UX 11.11

  tcl_platform(byteOrder) = bigEndian
  tcl_platform(machine)   = 9000/800
  tcl_platform(os)        = HP-UX
  tcl_platform(osVersion) = B.11.11
  tcl_platform(platform)  = unix
  tcl_platform(wordSize)  = 4

HP-UX 11.23 Itanium

  tcl_platform(byteOrder) = bigEndian
  tcl_platform(machine)   = ia64
  tcl_platform(os)        = HP-UX
  tcl_platform(osVersion) = B.11.23
  tcl_platform(platform)  = unix
  tcl_platform(wordSize)  = 4

HP-UX 11.31 parisc

  tcl_platform(byteOrder) = bigEndian
  tcl_platform(machine)   = 9000/800
  tcl_platform(os)        = HP-UX
  tcl_platform(osVersion) = B.11.31
  tcl_platform(platform)  = unix
  tcl_platform(wordSize)  = 4

  Linux

I've put the Linux entries together, annotated with processor, kernel, and distribution info. -- DJH

Linux Alpha kernel 2.2, distrib Redhat 6.2

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = alpha
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.2.19
 tcl_platform(platform)  = unix

Linux StrongARM kernel 2.4, distrib Debian 2.2

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = armv4l
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.0-test1-ac7-rmk1-crl2
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

Linux PowerPC kernel 2.4, distrib Debian 'woody'

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = ppc
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.16
 tcl_platform(platform)  = unix

Linux s/390x kernel 2.6, distrib SuSE Enterprise Server 10 SP 1

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = s390x
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.6.16.46-0.12-default
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

Linux SH4 kernel 2.4, distrib Debian unstable/testing

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = sh4
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.18-sh
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

Linux x86 kernel 2.4, distrib RedHat Enterprise Linux 3

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = ia64
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.21-47.EL
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 8

Linux x86 kernel 2.2, distrib Redhat 6.2

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.2.19
 tcl_platform(platform)  = unix

Linux x86 kernel 2.4, distrib Debian

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.7-win4lin
 tcl_platform(platform)  = unix

Linux x86 kernel 2.4 distrib Mandrake (8.1)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.8-26mdk
 tcl_platform(platform)  = unix

Linux x86, kernel 2.4.22, distrib Slackware

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.22
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

Linux x86, kernel 2.6.8, distrib Debian, Sarge (on PC with 1GHz AMD Athlon)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.6.8-2-386
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Linux x86, kernel 2.6.8, distrib Debian, Sarge (on PC with a classic Pentium 120)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i586
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.6.8-2-386
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Linux x86_64, kernel 2.6.8, distrib SUSE 9.2

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = x86_64
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.6.8-24.14-default
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 8

Linux x86, kernel 2.6.21.5, distrib Slackware 12.0

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i686
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.6.21.5
 tcl_platform(platform)  = unix
 tcl_platform(tip,268)   = 1
 tcl_platform(tip,280)   = 1
 tcl_platform(wordSize)  = 4

S/390 Linux

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = s390
 tcl_platform(os)        = Linux
 tcl_platform(osVersion) = 2.4.21-20.EL
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

  MacOS Classic / MacOS X

Mac OS 8

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = ppc
 tcl_platform(os)        = MacOS
 tcl_platform(osVersion) = 8.6
 tcl_platform(platform)  = macintosh

Mac OS 9

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = ppc
 tcl_platform(os)        = MacOS
 tcl_platform(osVersion) = 9.0
 tcl_platform(platform)  = macintosh

Mac OS X

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 1.3.7
 tcl_platform(platform)  = unix

Mac OS X, officially version 10.2.3, "Jaguar"

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 6.3
 tcl_platform(platform)  = unix

Mac OS X, 10.3.9, "Panther"

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 7.9.0
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.1, "Tiger"

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.1.0
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.3, "Tiger"

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.3.0
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.6

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.6.0
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.8 (PowerPC)

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.8.0
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.8 (Intel)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.8.1
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.4.10 (Intel)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 8.10.1
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(tip,268)   = 1
 tcl_platform(tip,280)   = 1
 tcl_platform(wordSize)  = 4

Mac OS X, 10.5.1 "Leopard" (PowerPC)

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = Power Macintosh
 tcl_platform(os)        = Darwin
 tcl_platform(osVersion) = 9.1.0
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 8

Mac OS X, 10.5.1 "Leopard" (Intel) - ActiveTcl 8.5.0

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = i386
 tcl_platform(os)          = Darwin
 tcl_platform(osVersion)   = 9.1.0
 tcl_platform(platform)    = unix
 tcl_platform(pointerSize) = 4
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 4

MacOS X 10.6.2 "Snow Leopard" (Intel) - ActiveTcl 8.6

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = i386
 tcl_platform(os)          = Darwin
 tcl_platform(osVersion)   = 10.2.0
 tcl_platform(platform)    = unix
 tcl_platform(pointerSize) = 4
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 4

MacOS X 10.7.1 "Lion" (Intel) - ActiveTcl 8.5.10

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = x86_64
 tcl_platform(os)          = Darwin
 tcl_platform(osVersion)   = 11.1.0
 tcl_platform(platform)    = unix
 tcl_platform(pointerSize) = 8
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 8

MacOS X 10.9.4 "Mavericks" (Intel) - tclkit 8.6.4

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = x86_64
 tcl_platform(os)            = Darwin
 tcl_platform(osVersion)     = 13.3.0
 tcl_platform(pathSeparator) = :
 tcl_platform(platform)      = unix
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 8

MacOS X 10.10 "Yosemite" (Intel) - ActiveTcl 8.6.4

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = x86_64
 tcl_platform(os)            = Darwin
 tcl_platform(osVersion)     = 14.3.0
 tcl_platform(pathSeparator) = :
 tcl_platform(platform)      = unix
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 8

MacOS X 10.11 "El Capitan" (Intel) - MacPorts 8.6.4

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = x86_64
 tcl_platform(os)            = Darwin
 tcl_platform(osVersion)     = 15.3.0
 tcl_platform(pathSeparator) = :
 tcl_platform(platform)      = unix
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 8

  BSD Variants

DragonFlyBSD 1.0A-RELEASE

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = DragonFly
 tcl_platform(osVersion) = 1.0A-RELEASE
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

FreeBSD 4.7-STABLE x86

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = FreeBSD
 tcl_platform(osVersion) = 4.7-STABLE
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

FreeBSD 4.8-STABLE x86

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = FreeBSD
 tcl_platform(osVersion) = 4.8-STABLE
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

NetBSD 1.6(I) x86

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = NetBSD
 tcl_platform(osVersion) = 1.6I
 tcl_platform(platform)  = unix

NetBSD 2.0.2 x86

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = NetBSD
 tcl_platform(osVersion) = 2.0.2
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

OpenBSD 3.0 x86

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i386
 tcl_platform(os)        = OpenBSD
 tcl_platform(osVersion) = 3.0
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

  Solaris

SunOS 4 / Solaris 1

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4m
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 4.1.3_U1
 tcl_platform(platform)  = unix

SPARC Solaris 2.6

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.6
 tcl_platform(platform)  = unix

Sparc Solaris 2.7

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.7
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1

Sparc Solaris 8

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.8
 tcl_platform(platform)  = unix

Intel Solaris 8

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = i86pc
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.8
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

Sparc Solaris 9 with threads enabled

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.9
 tcl_platform(platform)  = unix
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

Sparc Solaris 9 with threads and 64 bit enabled

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.9
 tcl_platform(platform)  = unix
 tcl_platform(pointerSize)  = 8
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 8

Sparc Solaris 9, without threads or 64 bit enabled, Tcl 8.5.4

 tcl_platform(byteOrder)   = bigEndian
 tcl_platform(machine)     = sun4u
 tcl_platform(os)          = SunOS
 tcl_platform(osVersion)   = 5.9
 tcl_platform(platform)    = unix
 tcl_platform(pointerSize) = 4
 tcl_platform(wordSize)    = 4

Sparc Solaris 10

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = sun4u
 tcl_platform(os)        = SunOS
 tcl_platform(osVersion) = 5.10
 tcl_platform(platform)  = unix
 tcl_platform(wordSize)  = 4

  Other UNIX

IRIX 6.5

 tcl_platform(byteOrder) = bigEndian
 tcl_platform(machine)   = IP32
 tcl_platform(os)        = IRIX
 tcl_platform(osVersion) = 6.5
 tcl_platform(platform)  = unix

Tru64 UNIX

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = alpha
 tcl_platform(os)        = OSF1
 tcl_platform(osVersion) = X5.1
 tcl_platform(platform)  = unix

  Windows

MSDN has documentation for the Microsoft Windows platforms [1]

CYGWIN_NT-5.1 (tclsh8.5.exe, Cygwin on Windows XP Professional)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.1
 tcl_platform(platform)  = unix

The last field changed from "windows" to "unix" in 2012-02.

Windows 3.1

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Win32s
 tcl_platform(osVersion) = 1.30
 tcl_platform(platform)  = windows

Win95

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows 95
 tcl_platform(osVersion) = 4.0
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Win98

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows 95
 tcl_platform(osVersion) = 4.10
 tcl_platform(platform)  = windows

WinNT

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 4.0
 tcl_platform(platform)  = windows

Win2000

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.0
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows XP Home

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.1
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows XP Professional

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(debug)     = 1
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.1
 tcl_platform(platform)  = windows

Windows XP Professional/Firefox 1.04 with Tcl/Tk Tclet Plugin (with [tk windowingsystem] = "win32")

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows Vista

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 6.0
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows 2003 x64 (64-bit) running 32-bit Tcl

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = intel
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.2
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows 2003 x64 (64-bit) running 64-bit Tcl

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = amd64
 tcl_platform(os)        = Windows NT
 tcl_platform(osVersion) = 5.2
 tcl_platform(platform)  = windows
 tcl_platform(wordSize)  = 4

Windows 7 32-bit

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = intel
 tcl_platform(os)          = Windows NT
 tcl_platform(osVersion)   = 6.1
 tcl_platform(pointerSize) = 4
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 4

Windows 7 Home Premium 64-bit

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = intel
 tcl_platform(os)          = Windows NT
 tcl_platform(osVersion)   = 6.1
 tcl_platform(platform)    = windows
 tcl_platform(pointerSize) = 4
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 4

Windows 8.0 64-bit

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = amd64
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 6.2
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 4

Windows 8.1 Pro 64-bit

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = amd64
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 6.3
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 4

Note that an older Tcl version will identify Windows 8.1 as osVersion 6.2. This is an artifact of the windows API.

Windows 10 Pro x64 (tclkit-8.6.4-win32-ix86.exe)

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = intel
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 10.0
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 4
 tcl_platform(wordSize)      = 4

Windows 10 Pro x64 (tclkit-8.6.4-win32-x86_64.exe)

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = amd64
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 10.0
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 8
 tcl_platform(wordSize)      = 4

Note: there is no way to obtain the bitsize of the OS, an important variable, e.g. when you're going to exec programs that exist in specific 32- and 64-bit versions. A quick and reliable method in distinguishing is by using the windows wmi framework as follows (but you could also use the twapi package):
 lindex [exec wmic computersystem get systemtype] 1

Responses: X86-based or x64-based

This was tested with following systems with 64-bit CPUs: Win XP 32-bit, Win7 32-bit and Win7 64-bit.

Windows 7 Home Premium 64-bit running 64-bit Tcl

 tcl_platform(byteOrder)   = littleEndian
 tcl_platform(machine)     = amd64
 tcl_platform(os)          = Windows NT
 tcl_platform(osVersion)   = 6.1
 tcl_platform(platform)    = windows
 tcl_platform(pointerSize) = 8
 tcl_platform(threaded)    = 1
 tcl_platform(wordSize)    = 4

Windows 2008 Server R2 64-bit

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = amd64
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 6.1
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 8
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 4

Windows/CE

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = arm
 tcl_platform(os)        = Windows CE
 tcl_platform(osVersion) = 3.0
 tcl_platform(platform)  = windows

Windows Mobile 2003SE (eTcl)

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = arm
 tcl_platform(os)        = Windows CE
 tcl_platform(osVersion) = 4.21
 tcl_platform(platform)  = windows
 tcl_platform(threaded)  = 1
 tcl_platform(wordSize)  = 4

  Other Platforms

OS/400 V5R1M0

 tcl_platform(byteOrder)     = bigEndian
 tcl_platform(host_platform) = unix
 tcl_platform(machine)       = PowerPC
 tcl_platform(os)            = OS/400
 tcl_platform(osVersion)     = V5R1M0
 tcl_platform(platform)      = java

QNX 6.3.0

 tcl_platform(byteOrder) = littleEndian
 tcl_platform(machine)   = x86pc
 tcl_platform(os)        = QNX
 tcl_platform(osVersion) = 6.3.0
 tcl_platform(platform)  = unix

  Eagle

Windows 7 Ultimate x86

 tcl_platform(byteOrder)     = littleEndian
 tcl_platform(machine)       = intel
 tcl_platform(os)            = Windows NT
 tcl_platform(osVersion)     = 6.1
 tcl_platform(pathSeparator) = ;
 tcl_platform(platform)      = windows
 tcl_platform(pointerSize)   = 4
 tcl_platform(threaded)      = 1
 tcl_platform(wordSize)      = 4


Usage tip: it's probably a mistake to "switch $::tcl_platform(os) ..." If you're having to distinguish different flavors of Unix or Windows from each other, you're likely better off determining the availability of the functionality you truly want, rather than trying to infer it from OS variation. In the Microsoft world, for example, service packs give different NT installations features that align them with 95, 98, ... Think of how autoconf performs run-time tests, rather than switching on uname.

For Tk since 8.4.2 there is also [tk windowingsystem], which tells you whether your Tk port is "win32", "x11", "aqua" or (MacOS) "classic". For UI issues that's better than asking for $tcl_platform(platform) and/or $tcl_platform(os), especially on MacOS X, where you have "aqua" as well as "x11" on the very same platform.

Note, the debug variable apparently is only available on Windows platforms when the Tcl library itself was compiled with the --enable-symbols flag.

There's a separate page called Generating a generic platform name, for discussion on how to massage the above information into a name which can be used as dirname to disambiguate shared libraries, etc.

Also potentially useful is the getWindowsAPIVendor proc which, on Windows, provides info regarding whether your underlying platform is Microsoft Windows, Wine or ReactOS.

[daneyul] - 2010-03-18 15:37:42

Last I checked, Windows 7 is no longer pre-release. Any one have any info on the codes returned by Win 7 32, 64, for the different versions (Home Premium, Ultimate, Pro) for those who don't have Win 7 systems at hand?

[JoGusto] - 2014-01-03

Win 7 Ultimate running Tcl 8.5 64-bit returns this:
   tcl_platform(byteOrder)   = littleEndian
   tcl_platform(machine)     = amd64
   tcl_platform(os)          = Windows NT
   tcl_platform(osVersion)   = 6.1
   tcl_platform(platform)    = windows
   tcl_platform(pointerSize) = 8
   tcl_platform(threaded)    = 1
   tcl_platform(wordSize)    = 4

(AFAIK, Win 7 Ultimate, Professional, etc, all return the same Windows version information for (os) and (osVersion))

AMG: Since Microsoft has chosen to use the LLP64 model for 64-bit Windows, $tcl_platform(wordSize) is 4 on both 32- and 64-bit platforms. Hardly useful. Thankfully, we have $tcl_platform(pointerSize) and $tcl_platform(machine) to disambiguate.

For my application, I'd like to know the rules of the platform (actually, the compiler used to build Tcl) for alignment and size of various C types.

Is a double aligned on a 4- or 8-byte boundary? 32- and 64-bit Linux disagree on this point (unless you use -malign-double), though I think 32- and 64-bit Windows both use 8-byte boundaries, at least when using MSVC.

[daneyul] - 2015-9-9

This list is getting woefully out of date. Wish I had the computers available to fill in the blanks but sadly I do not. Anyone able to add entries for:
 Mac:        Mountain Lion (OSX 10.8), Maverick (OSX 10.9), Yosemite (OSX 10.10) and El Capitain (OSX 10.11)
 Windows:    Windows 10

Torsten 2015.10.11 Added Maverick (OSX 10.9), systems folded to improve clarity

[kicka] - 2015-12-03 11:06:44

Added Android 5.0.2 Lollipop from my LG G2.