Admin/PLATFORMS
author paulson <lp15@cam.ac.uk>
Mon Jun 11 22:43:33 2018 +0100 (13 months ago)
changeset 68420 529d6b132c27
parent 68374 8740e1241555
child 69165 c360f3b603f8
permissions -rw-r--r--
tidier Cauchy proofs
     1 Multi-platform support of Isabelle
     2 ==================================
     3 
     4 Preamble
     5 --------
     6 
     7 The general programming model is that of a stylized ML + Scala + POSIX
     8 environment, with a minimum of system-specific code in user-space
     9 tools.
    10 
    11 The Isabelle system infrastructure provides some facilities to make
    12 this work, e.g. see the ML and Scala modules File and Path, or
    13 functions like Isabelle_System.bash.  The settings environment also
    14 provides some means for portability, e.g. the bash function
    15 "platform_path" to keep the impression that Windows/Cygwin adheres to
    16 Isabelle/POSIX standards, although Poly/ML and the JVM are native on
    17 Windows.
    18 
    19 When producing add-on tools, it is important to stay within this clean
    20 room of Isabelle, and refrain from non-portable access to operating
    21 system functions. The Isabelle environment uses peculiar scripts for
    22 GNU bash and perl as system glue: this style should be observed as far
    23 as possible.
    24 
    25 
    26 Supported platforms
    27 -------------------
    28 
    29 The following hardware and operating system platforms are officially
    30 supported by the Isabelle distribution (and bundled tools), with the
    31 following base-line versions (which have been selected to be neither
    32 too old nor too new):
    33 
    34   x86_64-linux      Ubuntu 12.04 LTS
    35 
    36   x86_64-darwin     Mac OS X 10.10 Yosemite (macbroy31 MacBookPro6,2)
    37                     Mac OS X 10.11 El Capitan (macbroy2 MacPro4,1)
    38                     macOS 10.12 Sierra (macbroy30 MacBookPro6,2)
    39                     macOS 10.13 High Sierra
    40 
    41   x86_64-windows    Windows 7
    42   x86_64-cygwin     Cygwin 2.10 https://isabelle.sketis.net/cygwin_2018 (x86_64/release)
    43 
    44 All of the above platforms are 100% supported by Isabelle -- end-users
    45 should not have to care about the differences (at least in theory).
    46 
    47 Exotic platforms like BSD, Solaris, NixOS are not supported.
    48 
    49 
    50 64 bit vs. 32 bit platform personality
    51 --------------------------------------
    52 
    53 Isabelle requires 64 bit hardware running a 64 bit operating
    54 system. Windows and Mac OS X allow x86 executables as well, but for
    55 Linux this requires separate installation of 32 bit shared
    56 libraries. The POSIX emulation on Windows via Cygwin64 works
    57 exclusively for x86_64.
    58 
    59 Poly/ML supports both for x86_64 and x86, and the latter is preferred
    60 for space and performance reasons. Java is always the x86_64 version
    61 on all platforms.
    62 
    63 Add-on executables are expected to work without manual user
    64 configuration. Each component settings script needs to determine the
    65 platform details appropriately.
    66 
    67 
    68 The Isabelle settings environment provides the following important
    69 variables to help configuring platform-dependent tools:
    70 
    71   ISABELLE_PLATFORM64  (potentially empty)
    72   ISABELLE_PLATFORM32  (potentially empty)
    73 
    74 Each can be empty, but not both at the same time. Using GNU bash
    75 notation, tools may express their platform preference, e.g. first 64
    76 bit and second 32 bit, or the opposite:
    77 
    78   "${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM32}"
    79   "${ISABELLE_PLATFORM32:-$ISABELLE_PLATFORM64}"
    80 
    81 
    82 There is a another set of settings for native Windows (instead of the
    83 POSIX emulation of Cygwin used before):
    84 
    85   ISABELLE_WINDOWS_PLATFORM64
    86   ISABELLE_WINDOWS_PLATFORM32
    87 
    88 These are always empty on Linux and Mac OS X, and non-empty on
    89 Windows. They can be used like this to prefer native Windows and then
    90 Unix (first 64 bit second 32 bit):
    91 
    92   "${ISABELLE_WINDOWS_PLATFORM64:-${ISABELLE_WINDOWS_PLATFORM32:-${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM32}}}"
    93 
    94 
    95 Dependable system tools
    96 -----------------------
    97 
    98 The following portable system tools can be taken for granted:
    99 
   100 * Scala on top of Java.  Isabelle/Scala irons out many oddities and
   101   portability issues of the Java platform.
   102 
   103 * GNU bash as uniform shell on all platforms. The POSIX "standard"
   104   shell /bin/sh does *not* work portably -- there are too many
   105   non-standard implementations of it. On Debian and Ubuntu /bin/sh is
   106   actually /bin/dash and introduces many oddities.
   107 
   108 * Perl as largely portable system programming language, with its
   109   fairly robust support for processes, signals, sockets etc.
   110 
   111 
   112 Known problems
   113 --------------
   114 
   115 * Mac OS X: If MacPorts is installed there is some danger that
   116   accidental references to its shared libraries are created
   117   (e.g. libgmp).  Use otool -L to check if compiled binaries also work
   118   without MacPorts.
   119 
   120 * Mac OS X: If MacPorts is installed and its version of Perl takes
   121   precedence over /usr/bin/perl in the PATH, then the end-user needs
   122   to take care of installing extra modules, e.g. for HTTP support.
   123   Such add-ons are usually included in Apple's /usr/bin/perl by
   124   default.
   125 
   126 * Common Unix tools like /bin/sh, /bin/kill, sed, ulimit are
   127   notoriously non-portable an should be avoided.
   128 
   129 * The traditional "uname" Unix tool only tells about its own executable
   130   format, not the underlying platform!