*.a
*.dll
*.dylib
*.exe
*.exp

*.lib

*.o
*.obj
*.pdb
*.res
*.sl
*.so
*/Makefile

html
libtommath/bn.ilg
libtommath/bn.ind
libtommath/pretty.build
libtommath/tommath.src
libtommath/*.log
libtommath/*.pdf
libtommath/*.pl
libtommath/*.sh
libtommath/doc/*
libtommath/tombc/*
libtommath/pre_gen/*
libtommath/pics/*
libtommath/mtest/*
libtommath/logs/*
libtommath/etc/*
libtommath/demo/*
libtommath/*.out
libtommath/*.tex
unix/autoMkindex.tcl
unix/dltest.marker
unix/tcl.pc
unix/tclIndex
unix/pkgs/*
win/Debug*
win/Release*

win/pkgs/*
win/coffbase.txt
win/tcl.hpj
win/nmhlp-out.txt

*/config.log
*/config.status
*/tclConfig.sh
*/tclsh*
*/tcltest*
*/versions.vc
*/version.vc


html
libtommath/bn.ilg
libtommath/bn.ind
libtommath/pretty.build
libtommath/tommath.src
libtommath/*.log
libtommath/*.pdf

unix/autoMkindex.tcl
unix/dltest.marker
unix/tcl.pc
unix/tclIndex
unix/pkgs/*
win/Debug*
win/Release*

win/pkgs/*

win/tcl.hpj
win/nmhlp-out.txt

    - name: "Linux/GCC/Shared: UTF_MAX=3"
      os: linux
      dist: xenial
      compiler: gcc
      env:
        - BUILD_DIR=unix
        - CFGOPT=CFLAGS=-DTCL_UTF_MAX=3







    - name: "Linux/GCC/Static"
      os: linux
      dist: xenial
      compiler: gcc
      env:
        - CFGOPT="--disable-shared"
        - BUILD_DIR=unix

    - name: "Linux/Clang/Shared: UTF_MAX=3"
      os: linux
      dist: xenial
      compiler: clang
      env:
        - BUILD_DIR=unix
        - CFGOPT=CFLAGS=-DTCL_UTF_MAX=3







    - name: "Linux/Clang/Static"
      os: linux
      dist: xenial
      compiler: clang
      env:
        - CFGOPT="--disable-shared"
        - BUILD_DIR=unix

      script: *mactest
# Test with mingw-w64 cross-compile
# Doesn't run tests because wine is only an imperfect Windows emulation
    - name: "Linux-cross-Windows/GCC/Shared/no test"
      os: linux
      dist: xenial
      compiler: x86_64-w64-mingw32-gcc
      addons: &mingw64
        apt:
          packages:
            - gcc-mingw-w64-base
            - binutils-mingw-w64-x86-64
            - gcc-mingw-w64-x86-64
            - gcc-mingw-w64
            - wine
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=x86_64-w64-mingw32 --enable-64bit"
      script: &crosstest
        - make all tcltest
        # Include a high visibility marker that tests are skipped outright
        - >
          echo "`tput setaf 3`SKIPPED TEST: CROSS COMPILING`tput sgr0`"
    - name: "Linux-cross-Windows/GCC/Shared/no test: UTF_MAX=6"
      os: linux
      dist: xenial
      compiler: x86_64-w64-mingw32-gcc
      addons: *mingw64
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=x86_64-w64-mingw32 --enable-64bit CFLAGS=-DTCL_UTF_MAX=6"
      script: *crosstest
    - name: "Linux-cross-Windows/GCC/Shared/no test: UTF_MAX=3"
      os: linux
      dist: xenial
      compiler: x86_64-w64-mingw32-gcc
      addons: *mingw64
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=x86_64-w64-mingw32 --enable-64bit CFLAGS=-DTCL_UTF_MAX=3"
      script: *crosstest
    - name: "Linux-cross-Windows/GCC/Static/no test"
      os: linux
      dist: xenial
      compiler: x86_64-w64-mingw32-gcc
      addons: *mingw64
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=x86_64-w64-mingw32 --enable-64bit --disable-shared"
      script: *crosstest
    - name: "Linux-cross-Windows/GCC/Debug/no test"
      os: linux
      dist: xenial
      compiler: x86_64-w64-mingw32-gcc
      addons: *mingw64
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=x86_64-w64-mingw32 --enable-64bit --enable-symbols"
      script: *crosstest
# Test with mingw-w64 (32 bit) cross-compile
# Doesn't run tests because wine is only an imperfect Windows emulation
    - name: "Linux-cross-Windows-32/GCC/Shared/no test"
      os: linux
      dist: xenial
      compiler: i686-w64-mingw32-gcc
      addons: &mingw32
        apt:
          packages:
            - gcc-mingw-w64-base
            - binutils-mingw-w64-i686
            - gcc-mingw-w64-i686
            - gcc-mingw-w64
            - gcc-multilib
            - wine
      env:
        - BUILD_DIR=win
        - CFGOPT=--host=i686-w64-mingw32
      script: *crosstest
    - name: "Linux-cross-Windows-32/GCC/Shared/no test: UTF_MAX=6"
      os: linux
      dist: xenial
      compiler: i686-w64-mingw32-gcc
      addons: *mingw32
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=i686-w64-mingw32 CFLAGS=-DTCL_UTF_MAX=6"
      script: *crosstest
    - name: "Linux-cross-Windows-32/GCC/Shared/no test: UTF_MAX=3"
      os: linux
      dist: xenial
      compiler: i686-w64-mingw32-gcc
      addons: *mingw32
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=i686-w64-mingw32 CFLAGS=-DTCL_UTF_MAX=3"
      script: *crosstest
    - name: "Linux-cross-Windows-32/GCC/Static/no test"
      os: linux
      dist: xenial
      compiler: i686-w64-mingw32-gcc
      addons: *mingw32
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=i686-w64-mingw32 --disable-shared"
      script: *crosstest
    - name: "Linux-cross-Windows-32/GCC/Debug/no test"
      os: linux
      dist: xenial
      compiler: i686-w64-mingw32-gcc
      addons: *mingw32
      env:
        - BUILD_DIR=win
        - CFGOPT="--host=i686-w64-mingw32 --enable-symbols"
      script: *crosstest
# Test on Windows with MSVC native
    - name: "Windows/MSVC/Shared"
      os: windows
      compiler: cl
      env: &vcenv
        - BUILD_DIR=win
        - VCDIR="/C/Program Files (x86)/Microsoft Visual Studio/2017/BuildTools/VC/Auxiliary/Build"

      compiler: cl
      env: *vcenv
      before_install: *vcpreinst
      install: []
      script:
        - cmd.exe /C 'vcvarsall.bat x64 && nmake OPTS=utfmax -f makefile.vc all tcltest'
        - cmd.exe /C 'vcvarsall.bat x64 && nmake OPTS=utfmax -f makefile.vc test'









    - name: "Windows/MSVC/Static"
      os: windows
      compiler: cl
      env: *vcenv
      before_install: *vcpreinst
      install: []
      script:

      compiler: cl
      env: *vcenv
      before_install: *vcpreinst
      install: []
      script:
        - cmd.exe /C 'vcvarsall.bat x86 && nmake OPTS=utfmax -f makefile.vc all tcltest'
        - cmd.exe /C 'vcvarsall.bat x86 && nmake OPTS=utfmax -f makefile.vc test'









    - name: "Windows/MSVC-x86/Static"
      os: windows
      compiler: cl
      env: *vcenv
      before_install: *vcpreinst
      install: []
      script:

    - name: "Windows/GCC/Shared: UTF_MAX=3"
      os: windows
      compiler: gcc
      env:
        - BUILD_DIR=win
        - CFGOPT="--enable-64bit CFLAGS=-DTCL_UTF_MAX=3"
      before_install: *makepreinst







    - name: "Windows/GCC/Static"
      os: windows
      compiler: gcc
      env:
        - BUILD_DIR=win
        - CFGOPT="--enable-64bit --disable-shared"
      before_install: *makepreinst

      before_install: *makepreinst
    - name: "Windows/GCC-x86/Shared: UTF_MAX=3"
      os: windows
      compiler: gcc
      env:
        - BUILD_DIR=win
        - CFGOPT="CFLAGS=-DTCL_UTF_MAX=3"







      before_install: *makepreinst
    - name: "Windows/GCC-x86/Static"
      os: windows
      compiler: gcc
      env:
        - BUILD_DIR=win
        - CFGOPT="--disable-shared"

# README:  Tcl

This is the **Tcl 9.0a0** source distribution.

You can get any source release of Tcl from [our distribution
site](https://sourceforge.net/projects/tcl/files/Tcl/).

[![Build Status](https://travis-ci.org/tcltk/tcl.svg?branch=master)](https://travis-ci.org/tcltk/tcl)

## Contents

2013-09-19 (bug fix)[3487626] segfaults in [dict] compilers (porter)

2013-09-19 (bug fix)[31661d2] mem leak in [lreplace] (ade,porter)

Many optmizations, improvements, and tightened stack management in bytecode.

--- Released 8.6.1, September 20, 2013 --- http://core.tcl.tk/tcl/ for details

2013-09-27 (enhancement) improved ::env synchronization (fellows)

2013-10-20 (bug fix)[2835313] segfault from
[apply {{} {while 1 {a {*}[return -level 0 -code continue]}}}] (fellows)

2013-10-22 (bug fix)[3556215] [scan %E%G%X] support (fellows)

2014-08-12 tzdata updated to Olson's tzdata2014f (kenny)

2014-08-17 (bug fix)[7d52e11] [info class subclasses oo::object] should
include ::oo::class (fellows)

2014-08-25 (TIP 429) New command [string cat] (leitgeb,ferrieux)

--- Released 8.6.2, August 27, 2014 --- http://core.tcl.tk/tcl/ for details

2014-08-28 (bug)[b9e1a3] Correct Method Search Order (nadkarni,fellows)
=> TclOO 1.0.3
        *** POTENTIAL INCOMPATIBILITY ***

2014-09-05 (bug)[ccc2c2] Regression [lreplace {} 1 1] (bron,fellows)

2014-10-31 (bug)[dcc034] restore [open comX: r+] (lll,nijtmans)

2014-11-05 (bug)[214cc0] Restore [lappend v] return value (sayers,porter)

2014-11-06 (bug)[5adc35] Stop forcing EOF to be permanent (porter)

--- Released 8.6.3, November 12, 2014 --- http://core.tcl.tk/tcl/ for details

2014-11-21 (bug)[743338] Win: socket error encoding (ladayaroslav,nijtmans)

2014-12-01 (bug) restore tbcload/tclcompiler support (kupries)

2014-12-03 (bug)[0c043a] Fix compiled [set var($) val] (porter)

2015-02-11 tzdata updated to Olson's tzdata2015a (venkat)

2015-02-20 (bug)[32b615] Fix compiled [lreplace] (lreplace-4.[345]) (aspect)

2015-03-10 (enhancement) Revise OS X notifier for better Cocoa (walzer)
        *** POTENTIAL INCOMPATIBILITY ***

--- Released 8.6.4, March 12, 2015 --- http://core.tcl.tk/tcl/ for details

2015-03-19 (bug)[e66e44] Win: Ctrl-C/Ctrl-Break in console not EOF (nadkarni)

2015-03-21 (bug)[d87cb1] Proper tailcall from compiled ensembles (sofer)

2015-04-23 (bug)[19ea02] Win: shared read from linked dirs (bogdan,oehhar)

2016-02-03 (bug)[25842c] stream [zlib deflate] fails with 0 input (ade,fellows)

2016-02-04 (bug)[3d96b7][593baa][cf74de] crashes in OO teardown (porter,fellows)

2016-02-22 (bug)[9b4702] [info exists env(missing)] kills trace (nijtmans)

--- Released 8.6.5, February 29, 2016 --- http://core.tcl.tk/tcl/ for details

2016-03-01 (bug)[803042] mem leak due to reference cycle (porter)

2016-03-08 (bug)[bbc304] reflected watch race condition (porter)

2016-03-17 (bug)[fadc99] compile-5.3 (rodriguez,porter)

2016-07-09 (bug)[1493a4] [namespace upvar] use of resolvers (beric,fellows)
        *** POTENTIAL INCOMPATIBILITY ***

2016-07-10 (bug)[da340d] integer division in clock math (nadkarni)

2016-07-20 tzdata updated to Olson's tzdata2016f (venkat)

--- Released 8.6.6, July 27, 2016 --- http://core.tcl.tk/tcl/ for details

2016-09-07 (bug)[c09edf] Bad caching with  custom resolver (neumann,nijtmans)

2016-09-07 (bug)[4dbdd9] Memleak in test var-8.3 (mr_calvin,porter)

2016-10-03 (bug)[2bf561] Allow empty command as alias target (yorick,nijtmans)
        *** POTENTIAL INCOMPATIBILITY ***

2017-06-26 (bug)[46f801] Repair autoloader fragility (porter)

2017-07-06 (bug)[adb198] Plug memleak in TclJoinPath (sebres,porter)

2017-07-17 (bug)[fb2208] Repeatable tclIndex generation (wiedemann,nijtmans)

--- Released 8.6.7, August 9, 2017 --- http://core.tcl.tk/tcl/ for details


















































2017-08-10 [array names -regexp] supports backrefs (goth)

2017-08-10 Fix gcc build failures due to #pragma placement (cassoff,fellows)

2017-08-29 (bug)[b50fb2] exec redir append stdout and stderr to file (coulter)

2017-12-06 (bug)[ce3a21] file normalize failure when tail is empty (porter)

2017-12-08 (new)[TIP 477] nmake build system reform (nadkarni)

2017-12-19 (bug)[586e71] EvalObjv exception handling at level #0 (sebres,porter)

--- Released 8.6.8, December 22, 2017 --- http://core.tcl.tk/tcl/ for details

2018-02-11 (enhance) stop blocking conversion of object to/from class (coulter)

2018-02-12 (enhance) NR-enable [package require] (coulter)

2018-02-14 (bug)[9fd5c6] crash in object deletion, test oo-11.5 (coulter)

2018-11-09 (bug)[35a8f1] overlong string length of some lists (owens)

2018-11-16 (bug)[00d04c] Repair [binary encode base64] (sebres)

- Released 8.6.9, November 16, 2018 - details at http://core.tcl-lang.org/tcl/ -

















































Changes to 8.7a1 include all changes to the 8.6 line through 8.6.7,

































































































































plus the following, which focuses on the high-level feature changes
in this changeset (new minor version) rather than bug fixes:

2016-03-17 (bug)[0b8c38] socket accept callbacks always in global ns (porter)
        *** POTENTIAL INCOMPATIBILITY ***

2016-07-01 Hack accommodations for legacy Itcl 3 disabled (porter)

2016-07-12 Make TCL_HASH_TYPE build-time configurable (nijtmans)

2016-07-19 (bug)[0363f0] Partial array search ID reform (porter)

2016-07-19 (feature removed) Tcl_ObjType "array search" unregistered (porter)
	*** POTENTIAL INCOMPATIBILITY for Tcl_GetObjType("array search") ***

2016-10-04 Server socket on port 0 chooses port supporting IPv4 * IPv6 (max)

2016-11-25 [array names -regexp] supports backrefs (goth)

2017-01-04 (TIP 456) New routine Tcl_OpenTcpServerEx() (limeboy)

2017-01-04 (TIP 459) New subcommand [package files] (nijtmans)

2017-01-16 threaded allocator initialization repair (vasiljevic,nijtmans)

2017-01-30 Add to Win shell builtins: assoc ftype move (ashok)

2017-03-31 TCL_MEM_DEBUG facilities better support 64-bit memory (nijtmans)

2017-04-13 \u escaped content in msg files converted to true utf-8 (nijtmans)

2017-05-18 (TIP 458) New epoll or kqueue notifiers are default (alborboz)

2017-05-31 Purge build support for SunOS-4.* (stu)

2017-06-22 (TIP 463) New option [regsub ... -command ...] (fellows)

2017-06-22 (TIP 470) Tcl_GetDefineContextObject();[oo::define [self]] (fellows)
=> TclOO 1.2.0

2017-06-23 (TIP 472) Support 0d as prefix of decimal numbers (iyer,griffin)

2017-08-31 (bug)[2a9465] http state 100 continue handling broken (oehlmann)

2017-09-02 (bug)[0e4d88] replace command, delete trace kills namespace (porter)

--- Released 8.7a1, September 8, 2017 --- http://core.tcl.tk/tcl/ for details

2018-03-12 (TIP 490) add oo support for msgcat => msgcat 1.7.0 (oehlmann)

2018-03-12 (TIP 499) custom locale preference list (oehlmann)
=> msgcat 1.7.0

- Released 8.7a3, Nov 30, 2018 --- http://core.tcl-lang.org/tcl/ for details -

*/

#if defined(_WIN32) && (!(defined(_CRT_SECURE_NO_WARNINGS)))
        #define _CRT_SECURE_NO_WARNINGS
#endif





#if defined(__APPLE__) || defined(IOAPI_NO_64)
// In darwin and perhaps other BSD variants off_t is a 64 bit value, hence no need for specific 64 bit functions
#define FOPEN_FUNC(filename, mode) fopen(filename, mode)
#define FTELLO_FUNC(stream) ftello(stream)
#define FSEEKO_FUNC(stream, offset, origin) fseeko(stream, offset, origin)
#else
#define FOPEN_FUNC(filename, mode) fopen64(filename, mode)
#define FTELLO_FUNC(stream) ftello64(stream)

                #define _LARGEFILE64_SOURCE
        #endif
        #ifndef _FILE_OFFSET_BIT
                #define _FILE_OFFSET_BIT 64
        #endif
#endif





#if defined(__APPLE__) || defined(IOAPI_NO_64)
// In darwin and perhaps other BSD variants off_t is a 64 bit value, hence no need for specific 64 bit functions
#define FOPEN_FUNC(filename, mode) fopen(filename, mode)
#define FTELLO_FUNC(stream) ftello(stream)
#define FSEEKO_FUNC(stream, offset, origin) fseeko(stream, offset, origin)
#else
#define FOPEN_FUNC(filename, mode) fopen64(filename, mode)
#define FTELLO_FUNC(stream) ftello64(stream)

'\"
'\" Copyright (c) 2018 Tcl Core Team
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
.so man.macros
.TH Tcl_InitSubsystems 3 8.7 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_InitSubsystems \- initialize the Tcl library.
.SH SYNOPSIS
.nf

As noted above, the \fItype\fR field is used to describe the interpretation of
the argument's value. The following values are acceptable values for
\fItype\fR:
.TP
\fBTCL_ARGV_CONSTANT\fR
.
The argument does not take any following value argument. If this argument is
present, the \fIsrcPtr\fR field (casted to \fIint\fR) is copied to the variable
pointed to by the \fIdstPtr\fR field. The \fIclientData\fR field is ignored.
.TP
\fBTCL_ARGV_END\fR
.
This value marks the end of all option descriptors in the table. All other
fields are ignored.
.TP

#define	NOERRN()	{if (ISERR()) return NULL;}	/* NOERR with retval */
#define	NOERRZ()	{if (ISERR()) return 0;}	/* NOERR with retval */
#define INSIST(c, e) do { if (!(c)) ERR(e); } while (0)	/* error if c false */
#define	NOTE(b)	(v->re->re_info |= (b))		/* note visible condition */
#define	EMPTYARC(x, y)	newarc(v->nfa, EMPTY, 0, x, y)

/* token type codes, some also used as NFA arc types */

#define	EMPTY	'n'		/* no token present */
#define	EOS	'e'		/* end of string */
#define	PLAIN	'p'		/* ordinary character */
#define	DIGIT	'd'		/* digit (in bound) */
#define	BACKREF	'b'		/* back reference */
#define	COLLEL	'I'		/* start of [. */
#define	ECLASS	'E'		/* start of [= */

declare 28 {
    Tcl_Obj *Tcl_DbNewStringObj(const char *bytes, size_t length,
	    const char *file, int line)
}
declare 29 {
    Tcl_Obj *Tcl_DuplicateObj(Tcl_Obj *objPtr)
}
# Removed in 9.0
#declare 30 {
#    void TclFreeObj(Tcl_Obj *objPtr)
#}

declare 31 {
    int Tcl_GetBoolean(Tcl_Interp *interp, const char *src, int *boolPtr)
}
declare 32 {
    int Tcl_GetBooleanFromObj(Tcl_Interp *interp, Tcl_Obj *objPtr,
	    int *boolPtr)
}

 * unix/tcl.spec	(1 LOC patch)
 * tools/tcl.hpj.in	(not patchlevel, for windows installer)
 */

#define TCL_MAJOR_VERSION   9
#define TCL_MINOR_VERSION   0
#define TCL_RELEASE_LEVEL   TCL_ALPHA_RELEASE
#define TCL_RELEASE_SERIAL  0

#define TCL_VERSION	    "9.0"
#define TCL_PATCH_LEVEL	    "9.0a0"

#if defined(RC_INVOKED)
/*
 * Utility macros: STRINGIFY takes an argument and wraps it in "" (double
 * quotation marks), JOIN joins two arguments.
 */

#define TCL_FILESYSTEM_VERSION_1	((Tcl_FSVersion) 0x1)

/*
 * struct Tcl_Filesystem:
 *
 * One such structure exists for each type (kind) of filesystem. It collects
 * together in one place all the functions that are part of the specific
 * filesystem. Tcl always accesses the filesystem through one of these
 * structures.
 *
 * Not all entries need be non-NULL; any which are NULL are simply ignored.
 * However, a complete filesystem should provide all of these functions. The
 * explanations in the structure show the importance of each function.
 */

typedef struct Tcl_Filesystem {
    const char *typeName;	/* The name of the filesystem. */
    size_t structureLength;	/* Length of this structure, so future binary
				 * compatibility can be assured. */
    Tcl_FSVersion version;	/* Version of the filesystem type. */
    Tcl_FSPathInFilesystemProc *pathInFilesystemProc;
				/* Function to check whether a path is in this
				 * filesystem. This is the most important
				 * filesystem function. */
    Tcl_FSDupInternalRepProc *dupInternalRepProc;
				/* Function to duplicate internal fs rep. May

				 * be NULL (but then fs is less efficient). */
    Tcl_FSFreeInternalRepProc *freeInternalRepProc;
				/* Function to free internal fs rep. Must be

				 * implemented if internal representations
				 * need freeing, otherwise it can be NULL. */
    Tcl_FSInternalToNormalizedProc *internalToNormalizedProc;
				/* Function to convert internal representation
				 * to a normalized path. Only required if the
				 * fs creates pure path objects with no
				 * string/path representation. */
    Tcl_FSCreateInternalRepProc *createInternalRepProc;
				/* Function to create a filesystem-specific
				 * internal representation. May be NULL if
				 * paths have no internal representation, or
				 * if the Tcl_FSPathInFilesystemProc for this
				 * filesystem always immediately creates an
				 * internal representation for paths it
				 * accepts. */
    Tcl_FSNormalizePathProc *normalizePathProc;
				/* Function to normalize a path.  Should be
				 * implemented for all filesystems which can
				 * have multiple string representations for
				 * the same path object. */
    Tcl_FSFilesystemPathTypeProc *filesystemPathTypeProc;
				/* Function to determine the type of a path in
				 * this filesystem. May be NULL. */
    Tcl_FSFilesystemSeparatorProc *filesystemSeparatorProc;
				/* Function to return the separator
				 * character(s) for this filesystem. Must be
				 * implemented. */
    Tcl_FSStatProc *statProc;	/* Function to process a 'Tcl_FSStat()' call.
				 * Must be implemented for any reasonable
				 * filesystem. */
    Tcl_FSAccessProc *accessProc;
				/* Function to process a 'Tcl_FSAccess()'
				 * call. Must be implemented for any
				 * reasonable filesystem. */
    Tcl_FSOpenFileChannelProc *openFileChannelProc;
				/* Function to process a
				 * 'Tcl_FSOpenFileChannel()' call. Must be
				 * implemented for any reasonable
				 * filesystem. */
    Tcl_FSMatchInDirectoryProc *matchInDirectoryProc;
				/* Function to process a
				 * 'Tcl_FSMatchInDirectory()'.  If not

				 * implemented, then glob and recursive copy
				 * functionality will be lacking in the
				 * filesystem. */
    Tcl_FSUtimeProc *utimeProc;	/* Function to process a 'Tcl_FSUtime()' call.
				 * Required to allow setting (not reading) of
				 * times with 'file mtime', 'file atime' and
				 * the open-r/open-w/fcopy implementation of
				 * 'file copy'. */
    Tcl_FSLinkProc *linkProc;	/* Function to process a 'Tcl_FSLink()' call.
				 * Should be implemented only if the
				 * filesystem supports links (reading or
				 * creating). */
    Tcl_FSListVolumesProc *listVolumesProc;
				/* Function to list any filesystem volumes
				 * added by this filesystem. Should be
				 * implemented only if the filesystem adds
				 * volumes at the head of the filesystem. */
    Tcl_FSFileAttrStringsProc *fileAttrStringsProc;
				/* Function to list all attributes strings
				 * which are valid for this filesystem. If not
				 * implemented the filesystem will not support
				 * the 'file attributes' command. This allows
				 * arbitrary additional information to be
				 * attached to files in the filesystem. */
    Tcl_FSFileAttrsGetProc *fileAttrsGetProc;
				/* Function to process a
				 * 'Tcl_FSFileAttrsGet()' call, used by 'file
				 * attributes'. */
    Tcl_FSFileAttrsSetProc *fileAttrsSetProc;
				/* Function to process a
				 * 'Tcl_FSFileAttrsSet()' call, used by 'file
				 * attributes'.  */
    Tcl_FSCreateDirectoryProc *createDirectoryProc;
				/* Function to process a
				 * 'Tcl_FSCreateDirectory()' call. Should be
				 * implemented unless the FS is read-only. */
    Tcl_FSRemoveDirectoryProc *removeDirectoryProc;
				/* Function to process a
				 * 'Tcl_FSRemoveDirectory()' call. Should be
				 * implemented unless the FS is read-only. */
    Tcl_FSDeleteFileProc *deleteFileProc;
				/* Function to process a 'Tcl_FSDeleteFile()'
				 * call. Should be implemented unless the FS
				 * is read-only. */
    Tcl_FSCopyFileProc *copyFileProc;
				/* Function to process a 'Tcl_FSCopyFile()'
				 * call. If not implemented Tcl will fall back

				 * on open-r, open-w and fcopy as a copying
				 * mechanism, for copying actions initiated in
				 * Tcl (not C). */
    Tcl_FSRenameFileProc *renameFileProc;
				/* Function to process a 'Tcl_FSRenameFile()'

				 * call. If not implemented, Tcl will fall
				 * back on a copy and delete mechanism, for
				 * rename actions initiated in Tcl (not C). */
    Tcl_FSCopyDirectoryProc *copyDirectoryProc;
				/* Function to process a
				 * 'Tcl_FSCopyDirectory()' call. If not
				 * implemented, Tcl will fall back on a
				 * recursive create-dir, file copy mechanism,
				 * for copying actions initiated in Tcl (not
				 * C). */
    Tcl_FSLstatProc *lstatProc;	/* Function to process a 'Tcl_FSLstat()' call.
				 * If not implemented, Tcl will attempt to use
				 * the 'statProc' defined above instead. */
    Tcl_FSLoadFileProc *loadFileProc;
				/* Function to process a 'Tcl_FSLoadFile()'
				 * call. If not implemented, Tcl will fall
				 * back on a copy to native-temp followed by a
				 * Tcl_FSLoadFile on that temporary copy. */
    Tcl_FSGetCwdProc *getCwdProc;
				/* Function to process a 'Tcl_FSGetCwd()'
				 * call. Most filesystems need not implement
				 * this. It will usually only be called once,
				 * if 'getcwd' is called before 'chdir'. May
				 * be NULL. */
    Tcl_FSChdirProc *chdirProc;	/* Function to process a 'Tcl_FSChdir()' call.
				 * If filesystems do not implement this, it
				 * will be emulated by a series of directory
				 * access checks. Otherwise, virtual
				 * filesystems which do implement it need only
				 * respond with a positive return result if
				 * the dirName is a valid directory in their
				 * filesystem. They need not remember the
				 * result, since that will be automatically
				 * remembered for use by GetCwd. Real
				 * filesystems should carry out the correct
				 * action (i.e. call the correct system
				 * 'chdir' api). If not implemented, then 'cd'
				 * and 'pwd' will fail inside the
				 * filesystem. */




} Tcl_Filesystem;

/*
 * The following definitions are used as values for the 'linkAction' flag to
 * Tcl_FSLink, or the linkProc of any filesystem. Any combination of flags can
 * be given. For link creation, the linkProc should create a link which
 * matches any of the types given.

 *				block in a (potentially multi-block) input
 *				stream. Tells the conversion routine to
 *				perform any finalization that needs to occur
 *				after the last byte is converted and then to
 *				reset to an initial state. If the source
 *				buffer contains the entire input stream to be
 *				converted, this flag should be set.
 * TCL_ENCODING_STOPONERROR -	If set, then the converter will return
 *				immediately upon encountering an invalid byte
 *				sequence or a source character that has no
 *				mapping in the target encoding. If clear, then
 *				the converter will skip the problem,
 *				substituting one or more "close" characters in
 *				the destination buffer and then continue to
 *				convert the source.
 * TCL_ENCODING_NO_TERMINATE - 	If set, Tcl_ExternalToUtf will not append a
 *				terminating NUL byte.  Knowing that it will
 *				not need space to do so, it will fill all
 *				dstLen bytes with encoded UTF-8 content, as
 *				other circumstances permit.  If clear, the
 *				default behavior is to reserve a byte in
 *				the dst space for NUL termination, and to
 *				append the NUL byte.
 * TCL_ENCODING_CHAR_LIMIT -	If set and dstCharsPtr is not NULL, then
 *				Tcl_ExternalToUtf takes the initial value
 *				of *dstCharsPtr is taken as a limit of the
 *				maximum number of chars to produce in the
 *				encoded UTF-8 content.  Otherwise, the
 *				number of chars produced is controlled only
 *				by other limiting factors.
 */

#define TCL_ENCODING_START		0x01
#define TCL_ENCODING_END		0x02
#define TCL_ENCODING_STOPONERROR	0x04
#define TCL_ENCODING_NO_TERMINATE	0x08
#define TCL_ENCODING_CHAR_LIMIT		0x10

/*
 *----------------------------------------------------------------------------
 * Override definitions for libtommath.
 */

typedef struct mp_int mp_int;
#define MP_INT_DECLARED
typedef unsigned int mp_digit;
#define MP_DIGIT_DECLARED
typedef unsigned TCL_WIDE_INT_TYPE mp_word;
#define MP_WORD_DECLARED

/*
 *----------------------------------------------------------------------------
 * Definitions needed for Tcl_ParseArgvObj routines.
 * Based on tkArgv.c.
 * Modifications from the original are copyright (c) Sam Bromley 2006
 */

#ifndef USE_TCL_STUBS
#   define Tcl_FindExecutable(arg) ((Tcl_FindExecutable)((const char *)(arg)))
#endif
#   define Tcl_MainEx Tcl_MainExW
    EXTERN TCL_NORETURN void Tcl_MainExW(int argc, wchar_t **argv,
	    Tcl_AppInitProc *appInitProc, Tcl_Interp *interp);
#endif
#if defined(USE_TCL_STUBS) && !defined(STATIC_BUILD)
#define Tcl_InitSubsystems() \
    TclInitStubTable(TclStubCall(0, NULL, NULL))
#define Tcl_FindExecutable(argv0) \
    TclInitStubTable(TclStubCall(1, (void *)argv0, NULL))
#define Tcl_SetPanicProc(panicProc) \
    TclInitStubTable(TclStubCall(2, (void *)panicProc, NULL))
#define TclZipfs_AppHook(argcp, argvp) \

#endif

#include "tclPlatDecls.h"

/*
 *----------------------------------------------------------------------------
 * The following declarations map ckalloc and ckfree to Tcl_Alloc and
 * Tcl_Free.
 */


#define ckalloc Tcl_Alloc







#define ckfree Tcl_Free
#define ckrealloc Tcl_Realloc
#define attemptckalloc Tcl_AttemptAlloc
#define attemptckrealloc Tcl_AttemptRealloc



#ifndef TCL_MEM_DEBUG

/*
 * If we are not using the debugging allocator, we should call the Tcl_Alloc,
 * et al. routines in order to guarantee that every module is using the same
 * memory allocator both inside and outside of the Tcl library.

	Tcl_DbIncrRefCount(objPtr, __FILE__, __LINE__)
#   undef Tcl_DecrRefCount
#   define Tcl_DecrRefCount(objPtr) \
	Tcl_DbDecrRefCount(objPtr, __FILE__, __LINE__)
#   undef Tcl_IsShared
#   define Tcl_IsShared(objPtr) \
	Tcl_DbIsShared(objPtr, __FILE__, __LINE__)



















#endif

/*
 * Macros and definitions that help to debug the use of Tcl objects. When
 * TCL_MEM_DEBUG is defined, the Tcl_New declarations are overridden to call
 * debugging versions of the object creation functions.
 */

	    }
	}
	break;
    case TCL_NUMBER_BIG:
	if (Tcl_GetBignumFromObj(interp, objv[1], &big) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (big.sign != MP_ZPOS) {
	    mp_clear(&big);
	    goto negarg;
	}
	break;
    default:
	if (TclGetWideIntFromObj(interp, objv[1], &w) != TCL_OK) {
	    return TCL_ERROR;

			return TCL_OK;
		    }
		    bytes++; numBytes--;
		}
	    }
	    goto unChanged;
	} else if (l == WIDE_MIN) {
	    TclInitBignumFromWideInt(&big, l);
	    goto tooLarge;
	}
	Tcl_SetObjResult(interp, Tcl_NewWideIntObj(-l));
	return TCL_OK;
    }

    if (type == TCL_NUMBER_DOUBLE) {

	    goto unChanged;
	}
	Tcl_SetObjResult(interp, Tcl_NewDoubleObj(-d));
	return TCL_OK;
    }

    if (type == TCL_NUMBER_BIG) {
	if (((const mp_int *) ptr)->sign != MP_ZPOS) {
	    Tcl_GetBignumFromObj(NULL, objv[1], &big);
	tooLarge:
	    mp_neg(&big, &big);
	    Tcl_SetObjResult(interp, Tcl_NewBignumObj(&big));
	} else {
	unChanged:
	    Tcl_SetObjResult(interp, objv[1]);

		    | (((Tcl_WideUInt) buffer[1]) << 48)
		    | (((Tcl_WideUInt) buffer[0]) << 56);
	}
	if (flags & BINARY_UNSIGNED) {
	    Tcl_Obj *bigObj = NULL;
	    mp_int big;


	    TclInitBignumFromWideUInt(&big, uwvalue);
	    bigObj = Tcl_NewBignumObj(&big);

	    return bigObj;
	}
	return Tcl_NewWideIntObj((Tcl_WideInt) uwvalue);

	/*
	 * Do not cache double values; they are already too large to use as
	 * keys and the values stored are utterly incompatible with the

	fields->year = year;
    }

    /*
     * Try an initial conversion in the Gregorian calendar.
     */

#if 0 /* BUG http://core.tcl.tk/tcl/tktview?name=da340d4f32 */
    ym1o4 = ym1 / 4;
#else
    /*
     * Have to make sure quotient is truncated towards 0 when negative.
     * See above bug for details. The casts are necessary.
     */
    if (ym1 >= 0)

    if (numBytes + 1 > 1) {
      /*
       * Don't use system stack (size of Tcl_Parse is ca. 400 bytes), so
       * many nested compilations (body enclosed in body) can cause abnormal
       * program termination with a stack overflow exception, bug [fec0c17d39].
       */
      Tcl_Parse *parsePtr = ckalloc(sizeof(Tcl_Parse));

      do {
	const char *next;

	if (TCL_OK != Tcl_ParseCommand(interp, p, numBytes, 0, parsePtr)) {
	    /*
	     * Compile bytecodes to report the parsePtr error at runtime.
	     */

	    Tcl_LogCommandInfo(interp, script, parsePtr->commandStart,
		    parsePtr->term + 1 - parsePtr->commandStart);
	    TclCompileSyntaxError(interp, envPtr);
	    ckfree(parsePtr);
	    return;
	}

#ifdef TCL_COMPILE_DEBUG
	/*
	 * If tracing, print a line for each top level command compiled.
	 * TODO: Suppress when numWords == 0 ?

	TclAdvanceLines(&envPtr->line, parsePtr->commandStart, p);
	TclAdvanceContinuations(&envPtr->line, &envPtr->clNext,
		p - envPtr->source);
	Tcl_FreeParse(parsePtr);
      } while (numBytes > 0);

      ckfree(parsePtr);
    }

    if (lastCmdIdx == -1) {
	/*
	 * Compiling the script yielded no bytecode.  The script must be all
	 * whitespace, comments, and empty commands.  Such scripts are defined
	 * to successfully produce the empty string result, so we emit the

/* 27 */
EXTERN Tcl_Obj *	Tcl_DbNewObj(const char *file, int line);
/* 28 */
EXTERN Tcl_Obj *	Tcl_DbNewStringObj(const char *bytes, size_t length,
				const char *file, int line);
/* 29 */
EXTERN Tcl_Obj *	Tcl_DuplicateObj(Tcl_Obj *objPtr);
/* Slot 30 is reserved */

/* 31 */
EXTERN int		Tcl_GetBoolean(Tcl_Interp *interp, const char *src,
				int *boolPtr);
/* 32 */
EXTERN int		Tcl_GetBooleanFromObj(Tcl_Interp *interp,
				Tcl_Obj *objPtr, int *boolPtr);
/* 33 */

    Tcl_Obj * (*tcl_DbNewByteArrayObj) (const unsigned char *bytes, size_t length, const char *file, int line); /* 23 */
    Tcl_Obj * (*tcl_DbNewDoubleObj) (double doubleValue, const char *file, int line); /* 24 */
    Tcl_Obj * (*tcl_DbNewListObj) (int objc, Tcl_Obj *const *objv, const char *file, int line); /* 25 */
    void (*reserved26)(void);
    Tcl_Obj * (*tcl_DbNewObj) (const char *file, int line); /* 27 */
    Tcl_Obj * (*tcl_DbNewStringObj) (const char *bytes, size_t length, const char *file, int line); /* 28 */
    Tcl_Obj * (*tcl_DuplicateObj) (Tcl_Obj *objPtr); /* 29 */
    void (*reserved30)(void);
    int (*tcl_GetBoolean) (Tcl_Interp *interp, const char *src, int *boolPtr); /* 31 */
    int (*tcl_GetBooleanFromObj) (Tcl_Interp *interp, Tcl_Obj *objPtr, int *boolPtr); /* 32 */
    unsigned char * (*tcl_GetByteArrayFromObj) (Tcl_Obj *objPtr, int *lengthPtr); /* 33 */
    int (*tcl_GetDouble) (Tcl_Interp *interp, const char *src, double *doublePtr); /* 34 */
    int (*tcl_GetDoubleFromObj) (Tcl_Interp *interp, Tcl_Obj *objPtr, double *doublePtr); /* 35 */
    void (*reserved36)(void);
    int (*tcl_GetInt) (Tcl_Interp *interp, const char *src, int *intPtr); /* 37 */

/* Slot 26 is reserved */
#define Tcl_DbNewObj \
	(tclStubsPtr->tcl_DbNewObj) /* 27 */
#define Tcl_DbNewStringObj \
	(tclStubsPtr->tcl_DbNewStringObj) /* 28 */
#define Tcl_DuplicateObj \
	(tclStubsPtr->tcl_DuplicateObj) /* 29 */

/* Slot 30 is reserved */
#define Tcl_GetBoolean \
	(tclStubsPtr->tcl_GetBoolean) /* 31 */
#define Tcl_GetBooleanFromObj \
	(tclStubsPtr->tcl_GetBooleanFromObj) /* 32 */
#define Tcl_GetByteArrayFromObj \
	(tclStubsPtr->tcl_GetByteArrayFromObj) /* 33 */
#define Tcl_GetDouble \

				 * points to an array of 256 shorts. If there
				 * is no corresponding character the encoding,
				 * the value in the matrix is 0x0000.
				 * malloc'd. */
} TableEncodingData;

/*
 * The following structures is the clientData for a dynamically-loaded,
 * escape-driven encoding that is itself comprised of other simpler encodings.
 * An example is "iso-2022-jp", which uses escape sequences to switch between
 * ascii, jis0208, jis0212, gb2312, and ksc5601. Note that "escape-driven"
 * does not necessarily mean that the ESCAPE character is the character used
 * for switching character sets.
 */

    char prefixBytes[256];	/* If a byte in the input stream is the first
				 * character of one of the escape sequences in
				 * the following array, the corresponding
				 * entry in this array is 1, otherwise it is
				 * 0. */
    int numSubTables;		/* Length of following array. */
    EscapeSubTable subTables[1];/* Information about each EscapeSubTable used
				 * by this encoding type. The actual size will
				 * be as large as necessary to hold all
				 * EscapeSubTables. */
} EscapeEncodingData;

/*
 * Constants used when loading an encoding file to identify the type of the
 * file.
 */

    0, 0, NULL, NULL, NULL, NULL, NULL
};

/*
 * A list of directories making up the "library path". Historically this
 * search path has served many uses, but the only one remaining is a base for
 * the encodingSearchPath above. If the application does not explicitly set
 * the encodingSearchPath, then it will be initialized by appending /encoding
 * to each directory in this "libraryPath".
 */

static ProcessGlobalValue libraryPath = {
    0, 0, NULL, NULL, TclpInitLibraryPath, NULL, NULL
};

static int encodingsInitialized = 0;

/*
 * Hash table that keeps track of all loaded Encodings. Keys are the string
 * names that represent the encoding, values are (Encoding *).
 */

static Tcl_HashTable encodingTable;
TCL_DECLARE_MUTEX(encodingMutex)

/*
 * The following are used to hold the default and current system encodings.
 * If NULL is passed to one of the conversion routines, the current setting of
 * the system encoding will be used to perform the conversion.
 */

static Tcl_Encoding defaultEncoding = NULL;
static Tcl_Encoding systemEncoding = NULL;
Tcl_Encoding tclIdentityEncoding = NULL;

/*

 *----------------------------------------------------------------------
 *
 * TclSetLibraryPath --
 *
 *	Keeps the per-thread copy of the library path current with changes to
 *	the global copy.
 *
 *	NOTE: this routine returns void, so there's no way to report the error
 *	that searchPath is not a valid list. In that case, this routine will
 *	silently do nothing.
 *
 *----------------------------------------------------------------------
 */

void
TclSetLibraryPath(
    Tcl_Obj *path)

}

/*
 *---------------------------------------------------------------------------
 *
 * FillEncodingFileMap --
 *
 *	Called to bring the encoding file map in sync with the current value
 *	of the encoding search path.
 *
 *	Scan the directories on the encoding search path, find the *.enc
 *	files, and store the found pathnames in a map associated with the
 *	encoding name.
 *
 *	In particular, if $dir is on the encoding search path, and the file
 *	$dir/foo.enc is found, then store a "foo" -> $dir entry in the map.
 *	Later, any need for the "foo" encoding will quickly * be able to
 *	construct the $dir/foo.enc pathname for reading the encoding data.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Entries are added to the encoding file map.
 *

    isLe.s = 1;
    Tcl_MutexLock(&encodingMutex);
    Tcl_InitHashTable(&encodingTable, TCL_STRING_KEYS);
    Tcl_MutexUnlock(&encodingMutex);

    /*
     * Create a few initial encodings. Note that the UTF-8 to UTF-8
     * translation is not a no-op, because it will turn a stream of improperly
     * formed UTF-8 into a properly formed stream.
     */

    type.encodingName	= NULL;
    type.toUtfProc	= BinaryProc;
    type.fromUtfProc	= BinaryProc;
    type.freeProc	= NULL;
    type.nullSize	= 1;

 * Results:
 *	Returns a token that represents the encoding. If the name didn't refer
 *	to any known or loadable encoding, NULL is returned. If NULL was
 *	returned, an error message is left in interp's result object, unless
 *	interp was NULL.
 *
 * Side effects:
 *	The new encoding type is entered into a table visible to all
 *	interpreters, keyed off the encoding's name. For each call to this
 *	function, there should eventually be a call to Tcl_FreeEncoding, so
 *	that the database can be cleaned up when encodings aren't needed
 *	anymore.
 *
 *-------------------------------------------------------------------------
 */

Tcl_Encoding
Tcl_GetEncoding(
    Tcl_Interp *interp,		/* Interp for error reporting, if not NULL. */

}

/*
 *---------------------------------------------------------------------------
 *
 * Tcl_FreeEncoding --
 *
 *	This function is called to release an encoding allocated by
 *	Tcl_CreateEncoding() or Tcl_GetEncoding().
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The reference count associated with the encoding is decremented and
 *	the encoding may be deleted if nothing is using it anymore.
 *
 *---------------------------------------------------------------------------
 */

void
Tcl_FreeEncoding(
    Tcl_Encoding encoding)
{
    Tcl_MutexLock(&encodingMutex);
    FreeEncoding(encoding);
    Tcl_MutexUnlock(&encodingMutex);
}

/*
 *----------------------------------------------------------------------
 *
 * FreeEncoding --
 *
 *	This function is called to release an encoding by functions that
 *	already have the encodingMutex.
 *
 * Results:
 *	None.
 *
 * Side effects:

 *	The reference count associated with the encoding is decremented and
 *	the encoding may be deleted if nothing is using it anymore.
 *
 *----------------------------------------------------------------------
 */

static void

}

/*
 *---------------------------------------------------------------------------
 *
 * Tcl_CreateEncoding --
 *
 *	This function is called to define a new encoding and the functions
 *	that are used to convert between the specified encoding and Unicode.
 *
 * Results:
 *	Returns a token that represents the encoding. If an encoding with the
 *	same name already existed, the old encoding token remains valid and
 *	continues to behave as it used to, and will eventually be garbage
 *	collected when the last reference to it goes away. Any subsequent
 *	calls to Tcl_GetEncoding with the specified name will retrieve the
 *	most recent encoding token.
 *
 * Side effects:
 *	The new encoding type is entered into a table visible to all
 *	interpreters, keyed off the encoding's name. For each call to this
 *	function, there should eventually be a call to Tcl_FreeEncoding, so
 *	that the database can be cleaned up when encodings aren't needed
 *	anymore.
 *
 *---------------------------------------------------------------------------
 */

Tcl_Encoding
Tcl_CreateEncoding(
    const Tcl_EncodingType *typePtr)

}

/*
 *-------------------------------------------------------------------------
 *
 * Tcl_UtfToExternalDString --
 *
 *	Convert a source buffer from UTF-8 into the specified encoding. If any
 *	of the bytes in the source buffer are invalid or cannot be represented
 *	in the target encoding, a default fallback character will be
 *	substituted.
 *
 * Results:
 *	The converted bytes are stored in the DString, which is then NULL
 *	terminated in an encoding-specific manner. The return value is a
 *	pointer to the value stored in the DString.
 *
 * Side effects:

 *
 * LoadEncodingFile --
 *
 *	Read a file that describes an encoding and create a new Encoding from
 *	the data.
 *
 * Results:
 *	The return value is the newly loaded Encoding, or NULL if the file
 *	didn't exist of was in the incorrect format. If NULL was returned, an
 *	error message is left in interp's result object, unless interp was
 *	NULL.
 *
 * Side effects:
 *	File read from disk.

 *
 *---------------------------------------------------------------------------
 */

static Tcl_Encoding
LoadEncodingFile(
    Tcl_Interp *interp,		/* Interp for error reporting, if not NULL. */
    const char *name)		/* The name of the encoding file on disk and
				 * also the name for new encoding. */
{
    Tcl_Channel chan = NULL;
    Tcl_Encoding encoding = NULL;
    int ch;

    chan = OpenEncodingFileChannel(interp, name);
    if (chan == NULL) {

}

/*
 *-------------------------------------------------------------------------
 *
 * LoadTableEncoding --
 *
 *	Helper function for LoadEncodingTable(). Loads a table to that
 *	converts between Unicode and some other encoding and creates an
 *	encoding (using a TableEncoding structure) from that information.
 *
 *	File contains binary data, but begins with a marker to indicate
 *	byte-ordering, so that same binary file can be read on either endian
 *	platforms.
 *
 * Results:
 *	The return value is the new encoding, or NULL if the encoding could
 *	not be created (because the file contained invalid data).
 *
 * Side effects:
 *	None.
 *
 *-------------------------------------------------------------------------
 */

static Tcl_Encoding
LoadTableEncoding(
    const char *name,		/* Name for new encoding. */
    int type,			/* Type of encoding (ENCODING_?????). */
    Tcl_Channel chan)		/* File containing new encoding. */
{
    Tcl_DString lineString;
    Tcl_Obj *objPtr;
    char *line;
    int i, hi, lo, numPages, symbol, fallback, len;

	    if (dataPtr->toUnicode[hi] != NULL) {
		dataPtr->prefixBytes[hi] = 1;
	    }
	}
    }

    /*
     * Invert toUnicode array to produce the fromUnicode array. Performs a
     * single malloc to get the memory for the array and all the pages needed
     * by the array. While reading in the toUnicode array, we remembered what
     * pages that would be needed for the fromUnicode array.
     */

    if (symbol) {
	used[0] = 1;
    }
    numPages = 0;
    for (hi = 0; hi < 256; hi++) {

		page[ch & 0xff] = (unsigned short) ((hi << 8) + lo);
	    }
	}
    }
    if (type == ENCODING_MULTIBYTE) {
	/*
	 * If multibyte encodings don't have a backslash character, define
	 * one. Otherwise, on Windows, native file names won't work because
	 * the backslash in the file name will map to the unknown character
	 * (question mark) when converting from UTF-8 to external encoding.
	 */

	if (dataPtr->fromUnicode[0] != NULL) {
	    if (dataPtr->fromUnicode[0]['\\'] == '\0') {
		dataPtr->fromUnicode[0]['\\'] = '\\';
	    }
	}
    }
    if (symbol) {
	/*
	 * Make a special symbol encoding that not only maps the symbol
	 * characters from their Unicode code points down into page 0, but
	 * also ensure that the characters on page 0 map to themselves. This
	 * is so that a symbol font can be used to display a simple string
	 * like "abcd" and have alpha, beta, chi, delta show up, rather than
	 * have "unknown" chars show up because strictly speaking the symbol
	 * font doesn't have glyphs for those low ASCII chars.
	 */

	page = dataPtr->fromUnicode[0];
	if (page == NULL) {
	    page = pageMemPtr;
	    dataPtr->fromUnicode[0] = page;
	}

    line = Tcl_DStringValue(&lineString);
    if (line[0] != 'R') {
	goto doneParse;
    }

    /*
     * Read lines from the encoding until EOF.
     */

    for (TclDStringClear(&lineString);
	    (len = Tcl_Gets(chan, &lineString)) != -1;
	    TclDStringClear(&lineString)) {
	const unsigned char *p;
	int to, from;

 *	None.
 *
 *-------------------------------------------------------------------------
 */

static Tcl_Encoding
LoadEscapeEncoding(
    const char *name,		/* Name for new encoding. */
    Tcl_Channel chan)		/* File containing new encoding. */
{
    int i;
    unsigned size;
    Tcl_DString escapeData;
    char init[16], final[16];
    EscapeEncodingData *dataPtr;

    memcpy(dst, src, srcLen);
    return result;
}

/*
 *-------------------------------------------------------------------------
 *
 * UtfExtToUtfIntProc --
 *
 *	Convert from UTF-8 to UTF-8. While converting null-bytes from the
 *	Tcl's internal representation (0xc0, 0x80) to the official
 *	representation (0x00). See UtfToUtfProc for details.
 *
 * Results:
 *	Returns TCL_OK if conversion was successful.

				 * stored in the output buffer as a result of
				 * the conversion. */
    int *dstCharsPtr,		/* Filled with the number of characters that
				 * correspond to the bytes stored in the
				 * output buffer. */
    int pureNullMode)		/* Convert embedded nulls from internal
				 * representation to real null-bytes or vice
				 * versa. */
{
    const char *srcStart, *srcEnd, *srcClose;
    const char *dstStart, *dstEnd;
    int result, numChars, charLimit = INT_MAX;
    Tcl_UniChar *chPtr = (Tcl_UniChar *) statePtr;

    if (flags & TCL_ENCODING_START) {
    	*statePtr = 0;
    }
    result = TCL_OK;

    srcStart = src;
    srcEnd = src + srcLen;
    srcClose = srcEnd;
    if ((flags & TCL_ENCODING_END) == 0) {
	srcClose -= TCL_UTF_MAX;
    }
    if (flags & TCL_ENCODING_CHAR_LIMIT) {
	charLimit = *dstCharsPtr;
    }

    dstStart = dst;
    dstEnd = dst + dstLen - TCL_UTF_MAX;

	     * incomplete char its bytes are made to represent themselves.
	     */

	    *chPtr = (unsigned char) *src;
	    src += 1;
	    dst += Tcl_UniCharToUtf(*chPtr, dst);
	} else {
	    int len = TclUtfToUniChar(src, chPtr);
	    src += len;

	    dst += Tcl_UniCharToUtf(*chPtr, dst);
#if TCL_UTF_MAX <= 4
	    if ((*chPtr >= 0xD800) && (len < 3)) {
		src += TclUtfToUniChar(src + len, chPtr);
		dst += Tcl_UniCharToUtf(*chPtr, dst);
	    }




#endif



	}
    }

    *srcReadPtr = src - srcStart;
    *dstWrotePtr = dst - dstStart;
    *dstCharsPtr = numChars;
    return result;

}

/*
 *---------------------------------------------------------------------------
 *
 * EscapeFreeProc --
 *
 *	This function is invoked when an EscapeEncodingData encoding is
 *	deleted. It deletes the memory used by the encoding.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory freed.
 *
 *---------------------------------------------------------------------------
 */

static void
EscapeFreeProc(
    ClientData clientData)	/* EscapeEncodingData that specifies

		wRemainder = w1 - w2*wQuotient;
		WIDE_RESULT(wRemainder);
	    }

	    Tcl_TakeBignumFromObj(NULL, value2Ptr, &big2);

	    /* TODO: internals intrusion */
	    if ((w1 > ((Tcl_WideInt) 0)) ^ (big2.sign == MP_ZPOS)) {
		/*
		 * Arguments are opposite sign; remainder is sum.
		 */

		TclInitBignumFromWideInt(&big1, w1);
		mp_add(&big2, &big1, &big2);
		mp_clear(&big1);
		BIG_RESULT(&big2);
	    }

	    /*
	     * Arguments are same sign; remainder is first operand.

	switch (type2) {
	case TCL_NUMBER_INT:
	    invalid = (*((const Tcl_WideInt *)ptr2) < 0);
	    break;
	case TCL_NUMBER_BIG:
	    Tcl_TakeBignumFromObj(NULL, value2Ptr, &big2);
	    invalid = big2.sign != MP_ZPOS;
	    mp_clear(&big2);
	    break;
	default:
	    /* Unused, here to silence compiler warning */
	    invalid = 0;
	}
	if (invalid) {

		switch (type1) {
		case TCL_NUMBER_INT:
		    zero = (*(const Tcl_WideInt *)ptr1 > 0);
		    break;
		case TCL_NUMBER_BIG:
		    Tcl_TakeBignumFromObj(NULL, valuePtr, &big1);
		    zero = (big1.sign == MP_ZPOS);
		    mp_clear(&big1);
		    break;
		default:
		    /* Unused, here to silence compiler warning. */
		    zero = 0;
		}
		if (zero) {

		return NULL;
	    }

	    negativeExponent = (w2 < 0);
	    oddExponent = (int) (w2 & (Tcl_WideInt)1);
	} else {
	    Tcl_TakeBignumFromObj(NULL, value2Ptr, &big2);
	    negativeExponent = big2.sign != MP_ZPOS;
	    mp_mod_2d(&big2, 1, &big2);
	    oddExponent = big2.used != 0;
	    mp_clear(&big2);
	}

	if (type1 == TCL_NUMBER_INT) {
	    w1 = *((const Tcl_WideInt *)ptr1);

		|| (Tcl_WideUInt)w2 >= (1<<28)) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "exponent too large", -1));
	    return GENERAL_ARITHMETIC_ERROR;
	}
	Tcl_TakeBignumFromObj(NULL, valuePtr, &big1);
	mp_init(&bigResult);
	mp_expt_d(&big1, (mp_digit)w2, &bigResult);
	mp_clear(&big1);
	BIG_RESULT(&bigResult);
    }

    case INST_ADD:
    case INST_SUB:
    case INST_MULT:

	case TCL_NUMBER_DOUBLE:
	    DOUBLE_RESULT(-(*((const double *) ptr)));
	case TCL_NUMBER_INT:
	    w = *((const Tcl_WideInt *) ptr);
	    if (w != WIDE_MIN) {
		WIDE_RESULT(-w);
	    }
	    TclInitBignumFromWideInt(&big, w);
	    break;
	default:
	    Tcl_TakeBignumFromObj(NULL, valuePtr, &big);
	}
	mp_neg(&big, &big);
	BIG_RESULT(&big);
    }

	    if (d2 > (double)WIDE_MAX) {
		return MP_LT;
	    }
	    w2 = (Tcl_WideInt) d2;
	    goto wideCompare;
	case TCL_NUMBER_BIG:
	    Tcl_TakeBignumFromObj(NULL, value2Ptr, &big2);
	    if (big2.sign != MP_ZPOS) {
		compare = MP_GT;
	    } else {
		compare = MP_LT;
	    }
	    mp_clear(&big2);
	    return compare;
	}

	    goto wideCompare;
	case TCL_NUMBER_BIG:
	    if (TclIsInfinite(d1)) {
		return (d1 > 0.0) ? MP_GT : MP_LT;
	    }
	    Tcl_TakeBignumFromObj(NULL, value2Ptr, &big2);
	    if ((d1 < (double)WIDE_MAX) && (d1 > (double)WIDE_MIN)) {
		if (big2.sign != MP_ZPOS) {
		    compare = MP_GT;
		} else {
		    compare = MP_LT;
		}
		mp_clear(&big2);
		return compare;
	    }

}

/*
 *----------------------------------------------------------------------
 *
 * TclGlob --
 *
 *	This procedure prepares arguments for the DoGlob call. It sets the
 *	separator string based on the platform, performs * tilde substitution,
 *	and calls DoGlob.
 *
 *	The interpreter's result, on entry to this function, must be a valid
 *	Tcl list (e.g. it could be empty), since we will lappend any new
 *	results to that list. If it is not a valid list, this function will
 *	fail to do anything very meaningful.
 *
 *	Note that if globFlags contains 'TCL_GLOBMODE_TAILS' then pathPrefix

	     * able to write something.  Either we did write something
	     * and wroteSome should be set, or there was nothing left to
	     * write in this call, and we've completed the BG flush.
	     * These are the two cases above.  If we get here, that means
	     * there is some kind failure in the writable event machinery.
	     *
	     * The tls extension indeed suffers from flaws in its channel
	     * event mgmt.  See http://core.tcl.tk/tcl/info/c31ca233ca.
	     * Until that patch is broadly distributed, disable the
	     * assertion checking here, so that programs using Tcl and
	     * tls can be debugged.

	    assert(!calledFromAsyncFlush);
	     */
	}

/*
 * tclIOUtil.c --
 *
 *	This file contains the implementation of Tcl's generic filesystem
 *	code, which supports a pluggable filesystem architecture allowing both
 *	platform specific filesystems and 'virtual filesystems'. All
 *	filesystem access should go through the functions defined in this
 *	file. Most of this code was contributed by Vince Darley.
 *
 *	Parts of this file are based on code contributed by Karl Lehenbauer,
 *	Mark Diekhans and Peter da Silva.
 *
 * Copyright (c) 1991-1994 The Regents of the University of California.
 * Copyright (c) 1994-1997 Sun Microsystems, Inc.
 * Copyright (c) 2001-2004 Vincent Darley.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.

#include <sys/statfs.h>
#endif
#endif

/*
 * struct FilesystemRecord --
 *
 * A filesystem record is used to keep track of each filesystem currently
 * registered with the core, in a linked list.
 */

typedef struct FilesystemRecord {
    ClientData clientData;	/* Client specific data for the new filesystem
				 * (can be NULL) */
    const Tcl_Filesystem *fsPtr;/* Pointer to filesystem dispatch table. */
    struct FilesystemRecord *nextPtr;
				/* The next filesystem registered to Tcl, or
				 * NULL if no more. */
    struct FilesystemRecord *prevPtr;
				/* The previous filesystem registered to Tcl,
				 * or NULL if no more. */
} FilesystemRecord;

/*
 * This structure holds per-thread private copy of the current directory
 * maintained by the global cwdPathPtr. This structure holds per-thread
 * private copies of some global data. This way we avoid most of the
 * synchronization calls which boosts performance, at cost of having to update
 * this information each time the corresponding epoch counter changes.
 */

typedef struct {
    int initialized;
    size_t cwdPathEpoch;


    size_t filesystemEpoch;
    Tcl_Obj *cwdPathPtr;



    ClientData cwdClientData;
    FilesystemRecord *filesystemList;
    size_t claims;
} ThreadSpecificData;

/*
 * Prototypes for functions defined later in this file.
 */

static Tcl_NRPostProc	EvalFileCallback;
static FilesystemRecord*FsGetFirstFilesystem(void);
static void		FsThrExitProc(ClientData cd);
static Tcl_Obj *	FsListMounts(Tcl_Obj *pathPtr, const char *pattern);
static void		FsAddMountsToGlobResult(Tcl_Obj *resultPtr,
			    Tcl_Obj *pathPtr, const char *pattern,
			    Tcl_GlobTypeData *types);
static void		FsUpdateCwd(Tcl_Obj *cwdObj, ClientData clientData);
static void		FsRecacheFilesystemList(void);
static void		Claim(void);
static void		Disclaim(void);

static void *		DivertFindSymbol(Tcl_Interp *interp,
			    Tcl_LoadHandle loadHandle, const char *symbol);
static void		DivertUnloadFile(Tcl_LoadHandle loadHandle);

/*
 * These form part of the native filesystem support. They are needed here
 * because we have a few native filesystem functions (which are the same for
 * win/unix) in this file. There is no need to place them in tclInt.h, because
 * they are not (and should not be) used anywhere else.
 */

MODULE_SCOPE const char *const		tclpFileAttrStrings[];
MODULE_SCOPE const TclFileAttrProcs	tclpFileAttrProcs[];

/*
 * Declare the native filesystem support. These functions should be considered
 * private to Tcl, and should really not be called directly by any code other
 * than this file (i.e. neither by Tcl's core nor by extensions). Similarly,
 * the old string-based Tclp... native filesystem functions should not be
 * called.
 *
 * The correct API to use now is the Tcl_FS... set of functions, which ensure
 * correct and complete virtual filesystem support.
 *
 * We cannot make all of these static, since some of them are implemented in
 * the platform-specific directories.
 */

static Tcl_FSFilesystemSeparatorProc NativeFilesystemSeparator;
static Tcl_FSFreeInternalRepProc NativeFreeInternalRep;
static Tcl_FSFileAttrStringsProc NativeFileAttrStrings;
static Tcl_FSFileAttrsGetProc	NativeFileAttrsGet;
static Tcl_FSFileAttrsSetProc	NativeFileAttrsSet;

/*




 * The only reason these functions are not static is that they are either


 * called by code in the native (win/unix) directories or they are actually
 * implemented in those directories. They should simply not be called by code



 * outside Tcl's native filesystem core i.e. they should be considered
 * 'static' to Tcl's filesystem code (if we ever built the native filesystem
 * support into a separate code library, this could actually be enforced).
 */

Tcl_FSFilesystemPathTypeProc	TclpFilesystemPathType;
Tcl_FSInternalToNormalizedProc	TclpNativeToNormalized;
Tcl_FSStatProc			TclpObjStat;
Tcl_FSAccessProc		TclpObjAccess;
Tcl_FSMatchInDirectoryProc	TclpMatchInDirectory;
Tcl_FSChdirProc			TclpObjChdir;
Tcl_FSLstatProc			TclpObjLstat;
Tcl_FSCopyFileProc		TclpObjCopyFile;
Tcl_FSDeleteFileProc		TclpObjDeleteFile;
Tcl_FSRenameFileProc		TclpObjRenameFile;
Tcl_FSCreateDirectoryProc	TclpObjCreateDirectory;
Tcl_FSCopyDirectoryProc		TclpObjCopyDirectory;
Tcl_FSRemoveDirectoryProc	TclpObjRemoveDirectory;
Tcl_FSLinkProc			TclpObjLink;
Tcl_FSListVolumesProc		TclpObjListVolumes;

/*
 * Define the native filesystem dispatch table. If necessary, it is ok to make
 * this non-static, but it should only be accessed by the functions actually
 * listed within it (or perhaps other helper functions of them). Anything
 * which is not part of this 'native filesystem implementation' should not be
 * delving inside here!
 */

const Tcl_Filesystem tclNativeFilesystem = {
    "native",
    sizeof(Tcl_Filesystem),
    TCL_FILESYSTEM_VERSION_2,
    TclNativePathInFilesystem,

    /* Needs casts since we're using version_2. */
    (Tcl_FSLoadFileProc *) TclpDlopen,
    (Tcl_FSGetCwdProc *) TclpGetNativeCwd,
    TclpObjChdir
};

/*
 * Define the tail of the linked list. Note that for unconventional uses of
 * Tcl without a native filesystem, we may in the future wish to modify the
 * current approach of hard-coding the native filesystem in the lookup list
 * 'filesystemList' below.
 *
 * We initialize the record so that it thinks one file uses it. This means it
 * will never be freed.
 */

static FilesystemRecord nativeFilesystemRecord = {
    NULL,
    &tclNativeFilesystem,
    NULL,
    NULL
};

/*
 * This is incremented each time we modify the linked list of filesystems. Any

 * time it changes, all cached filesystem representations are suspect and must
 * be freed. For multithreading builds, change of the filesystem epoch will
 * trigger cache cleanup in all threads.
 */

static size_t theFilesystemEpoch = 1;

/*
 * Stores the linked list of filesystems. A 1:1 copy of this list is also
 * maintained in the TSD for each thread. This is to avoid synchronization
 * issues.

 */

static FilesystemRecord *filesystemList = &nativeFilesystemRecord;
TCL_DECLARE_MUTEX(filesystemMutex)

/*
 * Used to implement Tcl_FSGetCwd in a file-system independent way.
 */

static Tcl_Obj *cwdPathPtr = NULL;
static size_t cwdPathEpoch = 0;
static ClientData cwdClientData = NULL;
TCL_DECLARE_MUTEX(cwdMutex)

static Tcl_ThreadDataKey fsDataKey;

/*
 * One of these structures is used each time we successfully load a file from
 * a file system by way of making a temporary copy of the file on the native
 * filesystem. We need to store both the actual unloadProc/clientData
 * combination which was used, and the original and modified filenames, so
 * that we can correctly undo the entire operation when we want to unload the
 * code.

 */

typedef struct {
    Tcl_LoadHandle loadHandle;
    Tcl_FSUnloadFileProc *unloadProcPtr;
    Tcl_Obj *divertedFile;
    const Tcl_Filesystem *divertedFilesystem;
    ClientData divertedFileNativeRep;
} FsDivertLoad;

/*
 * The following functions are obsolete string based APIs, and should be
 * removed in a future release (Tcl 9 would be a good time).

 */

/* Obsolete */
int
Tcl_Stat(
    const char *path,		/* Path of file to stat (in current CP). */
    struct stat *oldStyleBuf)	/* Filled with results of stat call. */
{
    int ret;
    Tcl_StatBuf buf;
    Tcl_Obj *pathPtr = Tcl_NewStringObj(path,-1);

    Tcl_IncrRefCount(pathPtr);

    }
    return ret;
}

/* Obsolete */
int
Tcl_Access(
    const char *path,		/* Path of file to access (in current CP). */

    int mode)			/* Permission setting. */
{
    int ret;
    Tcl_Obj *pathPtr = Tcl_NewStringObj(path,-1);

    Tcl_IncrRefCount(pathPtr);
    ret = Tcl_FSAccess(pathPtr,mode);
    Tcl_DecrRefCount(pathPtr);

    return ret;
}

/* Obsolete */
Tcl_Channel
Tcl_OpenFileChannel(
    Tcl_Interp *interp,		/* Interpreter for error reporting; can be
				 * NULL. */
    const char *path,		/* Name of file to open. */
    const char *modeString,	/* A list of POSIX open modes or a string such
				 * as "rw". */
    int permissions)		/* If the open involves creating a file, with
				 * what modes to create it? */
{
    Tcl_Channel ret;
    Tcl_Obj *pathPtr = Tcl_NewStringObj(path,-1);

    Tcl_IncrRefCount(pathPtr);
    ret = Tcl_FSOpenFileChannel(interp, pathPtr, modeString, permissions);
    Tcl_DecrRefCount(pathPtr);

    TclDStringAppendObj(cwdPtr, cwd);
    Tcl_DecrRefCount(cwd);
    return Tcl_DStringValue(cwdPtr);
}

int
Tcl_EvalFile(
    Tcl_Interp *interp,		/* Interpreter in which to process file. */
    const char *fileName)	/* Name of file to process. Tilde-substitution

				 * will be performed on this name. */
{
    int ret;
    Tcl_Obj *pathPtr = Tcl_NewStringObj(fileName,-1);

    Tcl_IncrRefCount(pathPtr);
    ret = Tcl_FSEvalFile(interp, pathPtr);
    Tcl_DecrRefCount(pathPtr);
    return ret;
}

/*
 * Now move on to the basic filesystem implementation.
 */

static void
FsThrExitProc(
    ClientData cd)
{
    ThreadSpecificData *tsdPtr = cd;
    FilesystemRecord *fsRecPtr = NULL, *tmpFsRecPtr = NULL;

    /*
     * Trash the cwd copy.
     */

    if (tsdPtr->cwdPathPtr != NULL) {
	Tcl_DecrRefCount(tsdPtr->cwdPathPtr);
	tsdPtr->cwdPathPtr = NULL;
    }
    if (tsdPtr->cwdClientData != NULL) {
	NativeFreeInternalRep(tsdPtr->cwdClientData);
    }

    /*
     * Trash the filesystems cache.
     */

    fsRecPtr = tsdPtr->filesystemList;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = fsRecPtr->nextPtr;
	fsRecPtr->fsPtr = NULL;
	Tcl_Free(fsRecPtr);

    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclFSCwdPointerEquals --
 *
 *	Check whether the current working directory is equal to the path
 *	given.
 *
 * Results:
 *	1 (equal) or 0 (un-equal) as appropriate.
 *
 * Side effects:
 *	If the paths are equal, but are not the same object, this method will


 *	modify the given pathPtrPtr to refer to the same object. In this case
 *	the object pointed to by pathPtrPtr will have its refCount
 *	decremented, and it will be adjusted to point to the cwd (with a new
 *	refCount).
 *


 *----------------------------------------------------------------------
 */

int
TclFSCwdPointerEquals(
    Tcl_Obj **pathPtrPtr)
{

	size_t len1, len2;
	const char *str1, *str2;

	str1 = TclGetStringFromObj(tsdPtr->cwdPathPtr, &len1);
	str2 = TclGetStringFromObj(*pathPtrPtr, &len2);
	if ((len1 == len2) && !memcmp(str1, str2, len1)) {
	    /*
	     * They are equal, but different objects. Update so they will be
	     * the same object in the future.
	     */

	    Tcl_DecrRefCount(*pathPtrPtr);
	    *pathPtrPtr = tsdPtr->cwdPathPtr;
	    Tcl_IncrRefCount(*pathPtrPtr);
	    return 1;
	} else {

    fsRecPtr = filesystemList;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = fsRecPtr;
	fsRecPtr = fsRecPtr->nextPtr;
    }

    /*
     * Refill the cache honouring the order.
     */

    list = NULL;
    fsRecPtr = tmpFsRecPtr;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = Tcl_Alloc(sizeof(FilesystemRecord));
	*tmpFsRecPtr = *fsRecPtr;

	    && (tsdPtr->filesystemEpoch != theFilesystemEpoch))) {
	FsRecacheFilesystemList();
    }
    return tsdPtr->filesystemList;
}

/*
 * The epoch can be changed by filesystems being added or removed, by changing
 * the "system encoding" and by env(HOME) changing.
 */

int
TclFSEpochOk(
    size_t filesystemEpoch)
{
    return (filesystemEpoch == 0 || filesystemEpoch == theFilesystemEpoch);

{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    return tsdPtr->filesystemEpoch;
}

/*
 * If non-NULL, clientData is owned by us and must be freed later.
 */

static void
FsUpdateCwd(
    Tcl_Obj *cwdObj,
    ClientData clientData)
{

    }

    if (cwdObj == NULL) {
	cwdPathPtr = NULL;
	cwdClientData = NULL;
    } else {
	/*
	 * This must be stored as string obj!
	 */

	cwdPathPtr = Tcl_NewStringObj(str, len);
	Tcl_IncrRefCount(cwdPathPtr);
	cwdClientData = TclNativeDupInternalRep(clientData);
    }

}

/*
 *----------------------------------------------------------------------
 *
 * TclFinalizeFilesystem --
 *
 *	Clean up the filesystem. After this, calls to all Tcl_FS... functions
 *	will fail.
 *
 *	We will later call TclResetFilesystem to restore the FS to a pristine
 *	state.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Frees any memory allocated by the filesystem.
 *
 *----------------------------------------------------------------------
 */

void
TclFinalizeFilesystem(void)
{
    FilesystemRecord *fsRecPtr;

    /*
     * Assumption that only one thread is active now. Otherwise we would need
     * to put various mutexes around this code.

     */

    if (cwdPathPtr != NULL) {
	Tcl_DecrRefCount(cwdPathPtr);
	cwdPathPtr = NULL;
	cwdPathEpoch = 0;
    }

     */

    fsRecPtr = filesystemList;
    while (fsRecPtr != NULL) {
	FilesystemRecord *tmpFsRecPtr = fsRecPtr->nextPtr;

	/*
	 * The native filesystem is static, so we don't free it.
	 */

	if (fsRecPtr != &nativeFilesystemRecord) {
	    Tcl_Free(fsRecPtr);
	}
	fsRecPtr = tmpFsRecPtr;
    }
    if (++theFilesystemEpoch == 0) {
	++theFilesystemEpoch;
    }
    filesystemList = NULL;

    /*
     * Now filesystemList is NULL. This means that any attempt to use the
     * filesystem is likely to fail.
     */

#ifdef _WIN32
    TclWinEncodingsCleanup();
#endif
}


}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSRegister --
 *
 *	Insert the filesystem function table at the head of the list of
 *	functions which are used during calls to all file-system operations.
 *	The filesystem will be added even if it is already in the list. (You

 *	can use Tcl_FSData to check if it is in the list, provided the
 *	ClientData used was not NULL).
 *
 *	Note that the filesystem handling is head-to-tail of the list. Each
 *	filesystem is asked in turn whether it can handle a particular
 *	request, until one of them says 'yes'. At that point no further

 *	filesystems are asked.
 *
 *	In particular this means if you want to add a diagnostic filesystem
 *	(which simply reports all fs activity), it must be at the head of the
 *	list: i.e. it must be the last registered.
 *
 * Results:
 *	Normally TCL_OK; TCL_ERROR if memory for a new node in the list could
 *	not be allocated.
 *
 * Side effects:
 *	Memory allocated and modifies the link list for filesystems.

 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSRegister(
    ClientData clientData,	/* Client specific data for this fs. */
    const Tcl_Filesystem *fsPtr)/* The filesystem record for the new fs. */
{
    FilesystemRecord *newFilesystemPtr;

    if (fsPtr == NULL) {
	return TCL_ERROR;
    }

    newFilesystemPtr = Tcl_Alloc(sizeof(FilesystemRecord));

    newFilesystemPtr->clientData = clientData;
    newFilesystemPtr->fsPtr = fsPtr;

    /*
     * Is this lock and wait strictly speaking necessary? Since any iterators
     * out there will have grabbed a copy of the head of the list and be
     * iterating away from that, if we add a new element to the head of the
     * list, it can't possibly have any effect on any of their loops. In fact
     * it could be better not to wait, since we are adjusting the filesystem
     * epoch, any cached representations calculated by existing iterators are
     * going to have to be thrown away anyway.
     *
     * However, since registering and unregistering filesystems is a very rare
     * action, this is not a very important point.
     */

    Tcl_MutexLock(&filesystemMutex);

    newFilesystemPtr->nextPtr = filesystemList;
    newFilesystemPtr->prevPtr = NULL;
    if (filesystemList) {
	filesystemList->prevPtr = newFilesystemPtr;
    }
    filesystemList = newFilesystemPtr;

    /*
     * Increment the filesystem epoch counter, since existing paths might
     * conceivably now belong to different filesystems.
     */

    if (++theFilesystemEpoch == 0) {
	++theFilesystemEpoch;
    }
    Tcl_MutexUnlock(&filesystemMutex);

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSUnregister --
 *
 *	Remove the passed filesystem from the list of filesystem function
 *	tables. It also ensures that the built-in (native) filesystem is not
 *	removable, although we may wish to change that decision in the future
 *	to allow a smaller Tcl core, in which the native filesystem is not
 *	used at all (we could, say, initialise Tcl completely over a network
 *	connection).
 *
 * Results:
 *	TCL_OK if the function pointer was successfully removed, TCL_ERROR
 *	otherwise.
 *
 * Side effects:
 *	Memory may be deallocated (or will be later, once no "path" objects
 *	refer to this filesystem), but the list of registered filesystems is
 *	updated immediately.

 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSUnregister(
    const Tcl_Filesystem *fsPtr)/* The filesystem record to remove. */
{
    int retVal = TCL_ERROR;
    FilesystemRecord *fsRecPtr;

    Tcl_MutexLock(&filesystemMutex);

    /*
     * Traverse the 'filesystemList' looking for the particular node whose
     * 'fsPtr' member matches 'fsPtr' and remove that one from the list.
     * Ensure that the "default" node cannot be removed.
     */

    fsRecPtr = filesystemList;
    while ((retVal == TCL_ERROR) && (fsRecPtr != &nativeFilesystemRecord)) {
	if (fsRecPtr->fsPtr == fsPtr) {
	    if (fsRecPtr->prevPtr) {
		fsRecPtr->prevPtr->nextPtr = fsRecPtr->nextPtr;
	    } else {
		filesystemList = fsRecPtr->nextPtr;
	    }
	    if (fsRecPtr->nextPtr) {
		fsRecPtr->nextPtr->prevPtr = fsRecPtr->prevPtr;
	    }

	    /*

	     * Increment the filesystem epoch counter, since existing paths
	     * might conceivably now belong to different filesystems. This
	     * should also ensure that paths which have cached the filesystem
	     * which is about to be deleted do not reference that filesystem
	     * (which would of course lead to memory exceptions).
	     */

	    if (++theFilesystemEpoch == 0) {
		++theFilesystemEpoch;
	    }

	    Tcl_Free(fsRecPtr);

}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSMatchInDirectory --
 *
 *	This routine is used by the globbing code to search a directory for
 *	all files which match a given pattern. The appropriate function for
 *	the filesystem to which pathPtr belongs will be called. If pathPtr
 *	does not belong to any filesystem and if it is NULL or the empty
 *	string, then we assume the pattern is to be matched in the current
 *	working directory. To avoid have the Tcl_FSMatchInDirectoryProc for
 *	each filesystem from having to deal with this issue, we create a
 *	pathPtr on the fly (equal to the cwd), and then remove it from the
 *	results returned. This makes filesystems easy to write, since they can
 *	assume the pathPtr passed to them is an ordinary path. In fact this
 *	means we could remove such special case handling from Tcl's native
 *	filesystems.
 *
 *	If 'pattern' is NULL, then pathPtr is assumed to be a fully specified

 *	path of a single file/directory which must be checked for existence
 *	and correct type.

 *
 * Results:
 *
 *	The return value is a standard Tcl result indicating whether an error
 *	occurred in globbing. Error messages are placed in interp, but good
 *	results are placed in the resultPtr given.

 *
 *	Recursive searches, e.g.
 *		glob -dir $dir -join * pkgIndex.tcl
 *	which must recurse through each directory matching '*' are handled
 *	internally by Tcl, by passing specific flags in a modified 'types'
 *	parameter. This means the actual filesystem only ever sees patterns
 *	which match in a single directory.
 *
 * Side effects:

 *	The interpreter may have an error message inserted into it.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSMatchInDirectory(
    Tcl_Interp *interp,		/* Interpreter to receive error messages, but
				 * may be NULL. */
    Tcl_Obj *resultPtr,		/* List object to receive results. */
    Tcl_Obj *pathPtr,		/* Contains path to directory to search. */

    const char *pattern,	/* Pattern to match against. */



    Tcl_GlobTypeData *types)	/* Object containing list of acceptable types.
				 * May be NULL. In particular the directory
				 * flag is very important. */
{
    const Tcl_Filesystem *fsPtr;
    Tcl_Obj *cwd, *tmpResultPtr, **elemsPtr;
    int resLength, i, ret = -1;

    if (types != NULL && (types->type & TCL_GLOB_TYPE_MOUNT)) {
	/*
	 * We don't currently allow querying of mounts by external code (a
	 * valuable future step), so since we're the only function that
	 * actually knows about mounts, this means we're being called
	 * recursively by ourself. Return no matches.
	 */

	return TCL_OK;
    }

    if (pathPtr != NULL) {
	fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);
    } else {
	fsPtr = NULL;
    }


    /*
     * Check if we've successfully mapped the path to a filesystem within
     * which to search.
     */

    if (fsPtr != NULL) {
	if (fsPtr->matchInDirectoryProc == NULL) {
	    Tcl_SetErrno(ENOENT);
	    return -1;
	}
	ret = fsPtr->matchInDirectoryProc(interp, resultPtr, pathPtr, pattern,
		types);
	if (ret == TCL_OK && pattern != NULL) {
	    FsAddMountsToGlobResult(resultPtr, pathPtr, pattern, types);
	}
	return ret;
    }


    /*
     * If the path isn't empty, we have no idea how to match files in a
     * directory which belongs to no known filesystem.
     */

    if (pathPtr != NULL && TclGetString(pathPtr)[0] != '\0') {
	Tcl_SetErrno(ENOENT);
	return -1;
    }

    /*
     * We have an empty or NULL path. This is defined to mean we must search
     * for files within the current 'cwd'. We therefore use that, but then
     * since the proc we call will return results which include the cwd we
     * must then trim it off the front of each path in the result. We choose
     * to deal with this here (in the generic code), since if we don't, every
     * single filesystem's implementation of Tcl_FSMatchInDirectory will have
     * to deal with it for us.
     */

    cwd = Tcl_FSGetCwd(NULL);
    if (cwd == NULL) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "glob couldn't determine the current working directory",

	Tcl_IncrRefCount(tmpResultPtr);
	ret = fsPtr->matchInDirectoryProc(interp, tmpResultPtr, cwd, pattern,
		types);
	if (ret == TCL_OK) {
	    FsAddMountsToGlobResult(tmpResultPtr, cwd, pattern, types);

	    /*
	     * Note that we know resultPtr and tmpResultPtr are distinct.
	     */

	    ret = Tcl_ListObjGetElements(interp, tmpResultPtr,
		    &resLength, &elemsPtr);
	    for (i=0 ; ret==TCL_OK && i<resLength ; i++) {
		ret = Tcl_ListObjAppendElement(interp, resultPtr,
			TclFSMakePathRelative(interp, elemsPtr[i], cwd));
	    }
	}
	TclDecrRefCount(tmpResultPtr);
    }
    Tcl_DecrRefCount(cwd);
    return ret;
}

/*
 *----------------------------------------------------------------------
 *
 * FsAddMountsToGlobResult --
 *
 *	This routine is used by the globbing code to take the results of a
 *	directory listing and add any mounted paths to that listing. This is
 *	required so that simple things like 'glob *' merge mounts and listings
 *	correctly.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Modifies the resultPtr.
 *
 *----------------------------------------------------------------------
 */

static void
FsAddMountsToGlobResult(
    Tcl_Obj *resultPtr,		/* The current list of matching paths; must
				 * not be shared! */
    Tcl_Obj *pathPtr,		/* The directory in question. */
    const char *pattern,	/* Pattern to match against. */
    Tcl_GlobTypeData *types)	/* Object containing list of acceptable types.
				 * May be NULL. In particular the directory
				 * flag is very important. */
{
    int mLength, gLength, i;
    int dir = (types == NULL || (types->type & TCL_GLOB_TYPE_DIR));
    Tcl_Obj *mounts = FsListMounts(pathPtr, pattern);

    if (mounts == NULL) {
	return;

	    }
	}
	if (!found && dir) {
	    Tcl_Obj *norm;
	    size_t len, mlen;

	    /*
	     * We know mElt is absolute normalized and lies inside pathPtr, so
	     * now we must add to the result the right representation of mElt,
	     * i.e. the representation which is relative to pathPtr.
	     */

	    norm = Tcl_FSGetNormalizedPath(NULL, pathPtr);
	    if (norm != NULL) {
		const char *path, *mount;

		mount = TclGetStringFromObj(mElt, &mlen);
		path = TclGetStringFromObj(norm, &len);
		if (path[len-1] == '/') {
		    /*
		     * Deal with the root of the volume.
		     */

		    len--;
		}
		len++;		/* account for '/' in the mElt [Bug 1602539] */


		mElt = TclNewFSPathObj(pathPtr, mount + len, mlen - len);
		Tcl_ListObjAppendElement(NULL, resultPtr, mElt);
	    }
	    /*
	     * No need to increment gLength, since we don't want to compare
	     * mounts against mounts.
	     */
	}
    }

  endOfMounts:
    Tcl_DecrRefCount(mounts);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSMountsChanged --
 *
 *	Notify the filesystem that the available mounted filesystems (or
 *	within any one filesystem type, the number or location of mount
 *	points) have changed.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The global filesystem variable 'theFilesystemEpoch' is incremented.
 *	The effect of this is to make all cached path representations invalid.
 *	Clearly it should only therefore be called when it is really required!
 *	There are a few circumstances when it should be called:
 *
 *	(1) when a new filesystem is registered or unregistered. Strictly
 *	speaking this is only necessary if the new filesystem accepts file
 *	paths as is (normally the filesystem itself is really a shell which
 *	hasn't yet had any mount points established and so its
 *	'pathInFilesystem' proc will always fail). However, for safety, Tcl
 *	always calls this for you in these circumstances.

 *
 *	(2) when additional mount points are established inside any existing
 *	filesystem (except the native fs)
 *
 *	(3) when any filesystem (except the native fs) changes the list of
 *	available volumes.
 *
 *	(4) when the mapping from a string representation of a file to a full,
 *	normalized path changes. For example, if 'env(HOME)' is modified, then

 *	any path containing '~' will map to a different filesystem location.
 *	Therefore all such paths need to have their internal representation
 *	invalidated.
 *
 *	Tcl has no control over (2) and (3), so any registered filesystem must
 *	make sure it calls this function when those situations occur.

 *
 *	(Note: the reason for the exception in 2,3 for the native filesystem
 *	is that the native filesystem by default claims all unknown files even
 *	if it really doesn't understand them or if they don't exist).

 *
 *----------------------------------------------------------------------
 */

void
Tcl_FSMountsChanged(
    const Tcl_Filesystem *fsPtr)
{
    /*
     * We currently don't do anything with this parameter. We could in the
     * future only invalidate files for this filesystem or otherwise take more
     * advanced action.
     */

    (void)fsPtr;

    /*
     * Increment the filesystem epoch counter, since existing paths might now
     * belong to different filesystems.
     */

    Tcl_MutexLock(&filesystemMutex);
    if (++theFilesystemEpoch == 0) {
	++theFilesystemEpoch;
    }
    Tcl_MutexUnlock(&filesystemMutex);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSData --
 *
 *	Retrieve the clientData field for the filesystem given, or NULL if
 *	that filesystem is not registered.
 *
 * Results:
 *	A clientData value, or NULL. Note that if the filesystem was
 *	registered with a NULL clientData field, this function will return
 *	that NULL value.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

ClientData
Tcl_FSData(
    const Tcl_Filesystem *fsPtr) /* The filesystem record to query. */

{
    ClientData retVal = NULL;
    FilesystemRecord *fsRecPtr = FsGetFirstFilesystem();

    /*
     * Traverse the list of filesystems look for a particular one. If found,
     * return that filesystem's clientData (originally provided when calling
     * Tcl_FSRegister).
     */

    while ((retVal == NULL) && (fsRecPtr != NULL)) {
	if (fsRecPtr->fsPtr == fsPtr) {
	    retVal = fsRecPtr->clientData;
	}
	fsRecPtr = fsRecPtr->nextPtr;
    }

    return retVal;
}

/*
 *---------------------------------------------------------------------------
 *
 * TclFSNormalizeToUniquePath --
 *
 *	Takes a path specification containing no ../, ./ sequences, and
 *	converts it into a unique path for the given platform. On Unix, this
 *	means the path must be free of symbolic links/aliases, and on Windows
 *	it means we want the long form, with that long form's case-dependence
 *	(which gives us a unique, case-dependent path).
 *

 * Results:
 *	The pathPtr is modified in place. The return value is the last byte
 *	offset which was recognised in the path string.
 *
 * Side effects:
 *	None (beyond the memory allocation for the result).
 *
 * Special notes:
 *	If the filesystem-specific normalizePathProcs can re-introduce ../, ./
 *	sequences into the path, then this function will not return the
 *	correct result. This may be possible with symbolic links on unix.
 *
 *	Important assumption: if startAt is non-zero, it must point to a
 *	directory separator that we know exists and is already normalized (so
 *	it is important not to point to the char just after the separator).
 *
 *---------------------------------------------------------------------------
 */

int
TclFSNormalizeToUniquePath(
    Tcl_Interp *interp,		/* Used for error messages. */
    Tcl_Obj *pathPtr,		/* The path to normalize in place. */

    int startAt)		/* Start at this char-offset. */




{
    FilesystemRecord *fsRecPtr, *firstFsRecPtr;

    size_t i;
    int isVfsPath = 0;
    const char *path;

    /*
     * Paths starting with a UNC prefix whose final character is a colon
     * are reserved for VFS use.  These names can not conflict with real
     * UNC paths per https://msdn.microsoft.com/en-us/library/gg465305.aspx
     * and rfc3986's definition of reg-name.
     *
     * We check these first to avoid useless calls to the native filesystem's
     * normalizePathProc.
     */
    path = TclGetStringFromObj(pathPtr, &i);

    if ( (i >= 3) && ( (path[0] == '/' && path[1] == '/')
		    || (path[0] == '\\' && path[1] == '\\') ) ) {
	for ( i = 2; ; i++) {
	    if (path[i] == '\0') break;
	    if (path[i] == path[0]) break;
	}
	--i;
	if (path[i] == ':') isVfsPath = 1;
    }

    /*
     * Call each of the "normalise path" functions in succession.
     */
    firstFsRecPtr = FsGetFirstFilesystem();

    Claim();

    if (!isVfsPath) {

	/*
	 * If we have a native filesystem handler, we call it first.  This is
	 * because the root of Tcl's filesystem is always a native filesystem
	 * (i.e., '/' on unix is native).
	 */

	for (fsRecPtr=firstFsRecPtr; fsRecPtr!=NULL; fsRecPtr=fsRecPtr->nextPtr) {
	    if (fsRecPtr->fsPtr != &tclNativeFilesystem) {
		continue;
	    }

	    /*
	     * TODO: Assume that we always find the native file system; it should
	     * always be there...
	     */

	    if (fsRecPtr->fsPtr->normalizePathProc != NULL) {
		startAt = fsRecPtr->fsPtr->normalizePathProc(interp, pathPtr,
			startAt);
	    }
	    break;
	}
    }

    for (fsRecPtr=firstFsRecPtr; fsRecPtr!=NULL; fsRecPtr=fsRecPtr->nextPtr) {

	/*
	 * Skip the native system next time through.
	 */

	if (fsRecPtr->fsPtr == &tclNativeFilesystem) {
	    continue;
	}

	if (fsRecPtr->fsPtr->normalizePathProc != NULL) {
	    startAt = fsRecPtr->fsPtr->normalizePathProc(interp, pathPtr,
		    startAt);
	}

	/*
	 * We could add an efficiency check like this:
	 *		if (retVal == length-of(pathPtr)) {break;}
	 * but there's not much benefit.
	 */
    }
    Disclaim();

    return startAt;
}

/*
 *---------------------------------------------------------------------------
 *
 * TclGetOpenMode --
 *
 *	This routine is an obsolete, limited version of TclGetOpenModeEx()
 *	below. It exists only to satisfy any extensions imprudently using it
 *	via Tcl's internal stubs table.
 *
 * Results:
 *	Same as TclGetOpenModeEx().
 *
 * Side effects:
 *	Same as TclGetOpenModeEx().
 *
 *---------------------------------------------------------------------------
 */

int
TclGetOpenMode(
    Tcl_Interp *interp,		/* Interpreter to use for error reporting -
				 * may be NULL. */
    const char *modeString,	/* Mode string, e.g. "r+" or "RDONLY CREAT" */
    int *seekFlagPtr)		/* Set this to 1 if the caller should seek to
				 * EOF during the opening of the file. */

{
    int binary = 0;
    return TclGetOpenModeEx(interp, modeString, seekFlagPtr, &binary);
}

/*
 *---------------------------------------------------------------------------
 *
 * TclGetOpenModeEx --
 *
 *	Computes a POSIX mode mask for opening a file, from a given string,
 *	and also sets flags to indicate whether the caller should seek to EOF
 *	after opening the file, and whether the caller should configure the
 *	channel for binary data.
 *
 * Results:
 *	On success, returns mode to pass to "open". If an error occurs, the
 *	return value is -1 and if interp is not NULL, sets interp's result
 *	object to an error message.
 *
 * Side effects:
 *	Sets the integer referenced by seekFlagPtr to 1 to tell the caller to
 *	seek to EOF after opening the file, or to 0 otherwise. Sets the

 *	integer referenced by binaryPtr to 1 to tell the caller to seek to
 *	configure the channel for binary data, or to 0 otherwise.
 *



 * Special note:
 *	This code is based on a prototype implementation contributed by Mark
 *	Diekhans.
 *
 *---------------------------------------------------------------------------
 */

int
TclGetOpenModeEx(
    Tcl_Interp *interp,		/* Interpreter to use for error reporting -
				 * may be NULL. */
    const char *modeString,	/* Mode string, e.g. "r+" or "RDONLY CREAT" */
    int *seekFlagPtr,		/* Set this to 1 if the caller should seek to
				 * EOF during the opening of the file. */
    int *binaryPtr)		/* Set this to 1 if the caller should
				 * configure the opened channel for binary
				 * operations. */
{
    int mode, modeArgc, c, i, gotRW;
    const char **modeArgv, *flag;
#define RW_MODES (O_RDONLY|O_WRONLY|O_RDWR)

    /*
     * Check for the simpler fopen-like access modes (e.g., "r"). They are
     * distinguished from the POSIX access modes by the presence of a
     * lower-case first letter.
     */

    *seekFlagPtr = 0;
    *binaryPtr = 0;
    mode = 0;

    /*
     * Guard against international characters before using byte oriented
     * routines.
     */

    if (!(modeString[0] & 0x80)
	    && islower(UCHAR(modeString[0]))) { /* INTL: ISO only. */
	switch (modeString[0]) {
	case 'r':
	    mode = O_RDONLY;
	    break;
	case 'w':
	    mode = O_WRONLY|O_CREAT|O_TRUNC;
	    break;
	case 'a':
	    /*
	     * Added O_APPEND for proper automatic seek-to-end-on-write by the
	     * OS. [Bug 680143]
	     */

	    mode = O_WRONLY|O_CREAT|O_APPEND;
	    *seekFlagPtr = 1;
	    break;
	default:
	    goto error;
	}
	i = 1;
	while (i<3 && modeString[i]) {
	    if (modeString[i] == modeString[i-1]) {
		goto error;
	    }
	    switch (modeString[i++]) {
	    case '+':
		/*
		 * Must remove the O_APPEND flag so that the seek command
		 * works. [Bug 1773127]
		 */

		mode &= ~(O_RDONLY|O_WRONLY|O_APPEND);
		mode |= O_RDWR;
		break;
	    case 'b':
		*binaryPtr = 1;

	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		    "illegal access mode \"%s\"", modeString));
	}
	return -1;
    }

    /*
     * The access modes are specified using a list of POSIX modes such as
     * O_CREAT.
     *
     * IMPORTANT NOTE: We rely on Tcl_SplitList working correctly when a NULL
     * interpreter is passed in.
     */

    if (Tcl_SplitList(interp, modeString, &modeArgc, &modeArgv) != TCL_OK) {
	if (interp != NULL) {
	    Tcl_AddErrorInfo(interp,
		    "\n    while processing open access modes \"");
	    Tcl_AddErrorInfo(interp, modeString);

}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSEvalFile, Tcl_FSEvalFileEx, TclNREvalFile --
 *
 *	Read in a file and process the entire file as one gigantic Tcl

 *	command. Tcl_FSEvalFile is Tcl_FSEvalFileEx without encoding argument.

 *	TclNREvalFile is an NRE-enabled version of Tcl_FSEvalFileEx.
 *
 * Results:
 *	A standard Tcl result, which is either the result of executing the
 *	file or an error indicating why the file couldn't be read.
 *
 * Side effects:
 *	Depends on the commands in the file. During the evaluation of the
 *	contents of the file, iPtr->scriptFile is made to point to pathPtr
 *	(the old value is cached and replaced when this function returns).
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSEvalFile(
    Tcl_Interp *interp,		/* Interpreter in which to process file. */
    Tcl_Obj *pathPtr)		/* Path of file to process. Tilde-substitution
				 * will be performed on this name. */

{
    return Tcl_FSEvalFileEx(interp, pathPtr, NULL);
}

int
Tcl_FSEvalFileEx(
    Tcl_Interp *interp,		/* Interpreter in which to process file. */
    Tcl_Obj *pathPtr,		/* Path of file to process. Tilde-substitution
				 * will be performed on this name. */

    const char *encodingName)	/* If non-NULL, then use this encoding for the
				 * file. NULL means use the system encoding. */
{
    size_t length;
	int result = TCL_ERROR;
    Tcl_StatBuf statBuf;
    Tcl_Obj *oldScriptFile;
    Interp *iPtr;
    const char *string;

	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		TclGetString(pathPtr), Tcl_PosixError(interp)));
	return result;
    }

    /*
     * The eofchar is \32 (^Z). This is the usual on Windows, but we effect
     * this cross-platform to allow for scripted documents. [Bug: 2040]
     */

    Tcl_SetChannelOption(interp, chan, "-eofchar", "\32 {}");

    /*
     * If the encoding is specified, set it for the channel. Else don't touch
     * it (and use the system encoding) Report error on unknown encoding.

     */

    if (encodingName != NULL) {
	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
		!= TCL_OK) {
	    Tcl_Close(interp,chan);
	    return result;
	}
    }

    objPtr = Tcl_NewObj();
    Tcl_IncrRefCount(objPtr);

    /*
     * Try to read first character of stream, so we can check for utf-8 BOM to
     * be handled especially.
     */

    if (Tcl_ReadChars(chan, objPtr, 1, 0) == TCL_IO_FAILURE) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		TclGetString(pathPtr), Tcl_PosixError(interp)));
	goto end;
    }
    string = TclGetString(objPtr);

    /*
     * If first character is not a BOM, append the remaining characters,
     * otherwise replace them. [Bug 3466099]
     */

    if (Tcl_ReadChars(chan, objPtr, -1,
	    memcmp(string, "\xef\xbb\xbf", 3)) == TCL_IO_FAILURE) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",

    iPtr = (Interp *) interp;
    oldScriptFile = iPtr->scriptFile;
    iPtr->scriptFile = pathPtr;
    Tcl_IncrRefCount(iPtr->scriptFile);
    string = TclGetStringFromObj(objPtr, &length);

    /*
     * TIP #280 Force the evaluator to open a frame for a sourced file.
     */

    iPtr->evalFlags |= TCL_EVAL_FILE;
    result = TclEvalEx(interp, string, length, 0, 1, NULL, string);

    /*
     * Now we have to be careful; the script may have changed the
     * iPtr->scriptFile value, so we must reset it without assuming it still

     * points to 'pathPtr'.
     */

    if (iPtr->scriptFile != NULL) {
	Tcl_DecrRefCount(iPtr->scriptFile);
    }
    iPtr->scriptFile = oldScriptFile;

    if (result == TCL_RETURN) {
	result = TclUpdateReturnInfo(iPtr);
    } else if (result == TCL_ERROR) {
	/*
	 * Record information telling where the error occurred.
	 */

	const char *pathString = TclGetStringFromObj(pathPtr, &length);
	unsigned limit = 150;
	int overflow = (length > limit);

	Tcl_AppendObjToErrorInfo(interp, Tcl_ObjPrintf(
		"\n    (file \"%.*s%s\" line %d)",
		(overflow ? limit : (unsigned)length), pathString,
		(overflow ? "..." : ""), Tcl_GetErrorLine(interp)));
    }

  end:
    Tcl_DecrRefCount(objPtr);
    return result;
}

int
TclNREvalFile(
    Tcl_Interp *interp,		/* Interpreter in which to process file. */
    Tcl_Obj *pathPtr,		/* Path of file to process. Tilde-substitution

				 * will be performed on this name. */
    const char *encodingName)	/* If non-NULL, then use this encoding for the
				 * file. NULL means use the system encoding. */
{
    Tcl_StatBuf statBuf;
    Tcl_Obj *oldScriptFile, *objPtr;
    Interp *iPtr;
    Tcl_Channel chan;
    const char *string;

		"couldn't read file \"%s\": %s",
		TclGetString(pathPtr), Tcl_PosixError(interp)));
	return TCL_ERROR;
    }
    TclPkgFileSeen(interp, TclGetString(pathPtr));

    /*
     * The eofchar is \32 (^Z). This is the usual on Windows, but we effect
     * this cross-platform to allow for scripted documents. [Bug: 2040]
     */

    Tcl_SetChannelOption(interp, chan, "-eofchar", "\32 {}");

    /*
     * If the encoding is specified, set it for the channel. Else don't touch
     * it (and use the system encoding) Report error on unknown encoding.

     */

    if (encodingName != NULL) {
	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
		!= TCL_OK) {
	    Tcl_Close(interp,chan);
	    return TCL_ERROR;
	}
    }

    objPtr = Tcl_NewObj();
    Tcl_IncrRefCount(objPtr);

    /*
     * Try to read first character of stream, so we can check for utf-8 BOM to
     * be handled especially.
     */

    if (Tcl_ReadChars(chan, objPtr, 1, 0) == TCL_IO_FAILURE) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		TclGetString(pathPtr), Tcl_PosixError(interp)));
	Tcl_DecrRefCount(objPtr);
	return TCL_ERROR;
    }
    string = TclGetString(objPtr);

    /*
     * If first character is not a BOM, append the remaining characters,
     * otherwise replace them. [Bug 3466099]
     */

    if (Tcl_ReadChars(chan, objPtr, -1,
	    memcmp(string, "\xef\xbb\xbf", 3)) == TCL_IO_FAILURE) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",

    iPtr = (Interp *) interp;
    oldScriptFile = iPtr->scriptFile;
    iPtr->scriptFile = pathPtr;
    Tcl_IncrRefCount(iPtr->scriptFile);

    /*
     * TIP #280: Force the evaluator to open a frame for a sourced file.
     */

    iPtr->evalFlags |= TCL_EVAL_FILE;
    TclNRAddCallback(interp, EvalFileCallback, oldScriptFile, pathPtr, objPtr,
	    NULL);
    return TclNREvalObjEx(interp, objPtr, 0, NULL, INT_MIN);
}

static int
EvalFileCallback(
    ClientData data[],
    Tcl_Interp *interp,
    int result)
{
    Interp *iPtr = (Interp *) interp;
    Tcl_Obj *oldScriptFile = data[0];
    Tcl_Obj *pathPtr = data[1];
    Tcl_Obj *objPtr = data[2];

    /*
     * Now we have to be careful; the script may have changed the
     * iPtr->scriptFile value, so we must reset it without assuming it still

     * points to 'pathPtr'.
     */

    if (iPtr->scriptFile != NULL) {
	Tcl_DecrRefCount(iPtr->scriptFile);
    }
    iPtr->scriptFile = oldScriptFile;

    if (result == TCL_RETURN) {
	result = TclUpdateReturnInfo(iPtr);
    } else if (result == TCL_ERROR) {
	/*
	 * Record information telling where the error occurred.
	 */

	size_t length;
	const char *pathString = TclGetStringFromObj(pathPtr, &length);
	const unsigned int limit = 150;
	int overflow = (length > limit);

}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetErrno --
 *
 *	Gets the current value of the Tcl error code variable. This is
 *	currently the global variable "errno" but could in the future change
 *	to something else.
 *
 * Results:
 *	The value of the Tcl error code variable.
 *
 * Side effects:
 *	None. Note that the value of the Tcl error code variable is UNDEFINED
 *	if a call to Tcl_SetErrno did not precede this call.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetErrno(void)
{
    /*
     * On some platforms, errno is really a thread local (implemented by the C
     * library).
     */

    return errno;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetErrno --
 *
 *	Sets the Tcl error code variable to the supplied value. On some saner
 *	platforms this is actually a thread-local (this is implemented in the
 *	C library) but this is *really* unsafe to assume!
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Modifies the value of the Tcl error code variable.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_SetErrno(
    int err)			/* The new value. */
{
    /*
     * On some platforms, errno is really a thread local (implemented by the C
     * library).
     */

    errno = err;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_PosixError --
 *
 *	This function is typically called after UNIX kernel calls return
 *	errors. It stores machine-readable information about the error in
 *	errorCode field of interp and returns an information string for the
 *	caller's use.
 *
 * Results:
 *	The return value is a human-readable string describing the error.
 *
 * Side effects:
 *	The errorCode field of the interp is set.
 *
 *----------------------------------------------------------------------
 */

const char *
Tcl_PosixError(
    Tcl_Interp *interp)		/* Interpreter whose errorCode field is to be
				 * set. */
{
    const char *id, *msg;

    msg = Tcl_ErrnoMsg(errno);
    id = Tcl_ErrnoId();
    if (interp) {
	Tcl_SetErrorCode(interp, "POSIX", id, msg, NULL);
    }
    return msg;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSStat --

 *
 *	This function replaces the library version of stat and lsat.
 *
 *	The appropriate function for the filesystem to which pathPtr belongs
 *	will be called.
 *
 * Results:
 *	See stat documentation.
 *
 * Side effects:
 *	See stat documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSStat(
    Tcl_Obj *pathPtr,		/* Path of file to stat (in current CP). */

    Tcl_StatBuf *buf)		/* Filled with results of stat call. */

{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL && fsPtr->statProc != NULL) {
	return fsPtr->statProc(pathPtr, buf);
    }
    Tcl_SetErrno(ENOENT);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSLstat --

 *
 *	This function replaces the library version of lstat. The appropriate
 *	function for the filesystem to which pathPtr belongs will be called.
 *	If no 'lstat' function is listed, but a 'stat' function is, then Tcl
 *	will fall back on the stat function.
 *
 * Results:
 *	See lstat documentation.
 *
 * Side effects:
 *	See lstat documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSLstat(
    Tcl_Obj *pathPtr,		/* Path of file to stat (in current CP). */

    Tcl_StatBuf *buf)		/* Filled with results of stat call. */
{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL) {
	if (fsPtr->lstatProc != NULL) {
	    return fsPtr->lstatProc(pathPtr, buf);
	}
	if (fsPtr->statProc != NULL) {
	    return fsPtr->statProc(pathPtr, buf);
	}
    }
    Tcl_SetErrno(ENOENT);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSAccess --
 *


 *	This function replaces the library version of access. The appropriate
 *	function for the filesystem to which pathPtr belongs will be called.
 *
 * Results:
 *	See access documentation.
 *
 * Side effects:
 *	See access documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSAccess(
    Tcl_Obj *pathPtr,		/* Path of file to access (in current CP). */
    int mode)			/* Permission setting. */
{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL && fsPtr->accessProc != NULL) {
	return fsPtr->accessProc(pathPtr, mode);
    }
    Tcl_SetErrno(ENOENT);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSOpenFileChannel --
 *
 *	The appropriate function for the filesystem to which pathPtr belongs
 *	will be called.
 *
 * Results:
 *	The new channel or NULL, if the named file could not be opened.
 *
 * Side effects:
 *	May open the channel and may cause creation of a file on the file
 *	system.
 *
 *----------------------------------------------------------------------
 */

Tcl_Channel
Tcl_FSOpenFileChannel(
    Tcl_Interp *interp,		/* Interpreter for error reporting; can be
				 * NULL. */
    Tcl_Obj *pathPtr,		/* Name of file to open. */
    const char *modeString,	/* A list of POSIX open modes or a string such
				 * as "rw". */
    int permissions)		/* If the open involves creating a file, with
				 * what modes to create it? */
{
    const Tcl_Filesystem *fsPtr;
    Tcl_Channel retVal = NULL;



    /*
     * We need this just to ensure we return the correct error messages under
     * some circumstances.
     */

    if (Tcl_FSGetNormalizedPath(interp, pathPtr) == NULL) {
	return NULL;
    }

    fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);
    if (fsPtr != NULL && fsPtr->openFileChannelProc != NULL) {
	int mode, seekFlag, binary;

	/*
	 * Parse the mode, picking up whether we want to seek to start with
	 * and/or set the channel automatically into binary mode.
	 */

	mode = TclGetOpenModeEx(interp, modeString, &seekFlag, &binary);
	if (mode == -1) {
	    return NULL;
	}

	/*
	 * Do the actual open() call.
	 */

	retVal = fsPtr->openFileChannelProc(interp, pathPtr, mode,
		permissions);
	if (retVal == NULL) {
	    return NULL;
	}

	/*
	 * Apply appropriate flags parsed out above.
	 */

	if (seekFlag && Tcl_Seek(retVal, (Tcl_WideInt) 0, SEEK_END)
		< (Tcl_WideInt) 0) {
	    if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"could not seek to end of file while opening \"%s\": %s",

}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSUtime --
 *



 *	This function replaces the library version of utime. The appropriate
 *	function for the filesystem to which pathPtr belongs will be called.
 *
 * Results:
 *	See utime documentation.
 *
 * Side effects:
 *	See utime documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSUtime(
    Tcl_Obj *pathPtr,		/* File to change access/modification
				 * times. */
    struct utimbuf *tval)	/* Structure containing access/modification
				 * times to use. Should not be modified. */
{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL && fsPtr->utimeProc != NULL) {
	return fsPtr->utimeProc(pathPtr, tval);
    }
    /* TODO: set errno here? Tcl_SetErrno(ENOENT); */
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * NativeFileAttrStrings --
 *
 *	This function implements the platform dependent 'file attributes'
 *	subcommand, for the native filesystem, for listing the set of possible
 *	attribute strings. This function is part of Tcl's native filesystem
 *	support, and is placed here because it is shared by Unix and Windows
 *	code.
 *
 * Results:
 *	An array of strings
 *
 * Side effects:
 *	None.
 *

}

/*
 *----------------------------------------------------------------------
 *
 * NativeFileAttrsGet --
 *
 *	This function implements the platform dependent 'file attributes'
 *	subcommand, for the native filesystem, for 'get' operations. This
 *	function is part of Tcl's native filesystem support, and is placed
 *	here because it is shared by Unix and Windows code.
 *
 * Results:
 *	Standard Tcl return code. The object placed in objPtrRef (if TCL_OK


 *	was returned) is likely to have a refCount of zero. Either way we must
 *	either store it somewhere (e.g. the Tcl result), or Incr/Decr its
 *	refCount to ensure it is properly freed.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
NativeFileAttrsGet(
    Tcl_Interp *interp,		/* The interpreter for error reporting. */
    int index,			/* index of the attribute command. */
    Tcl_Obj *pathPtr,		/* path of file we are operating on. */
    Tcl_Obj **objPtrRef)	/* for output. */
{
    return tclpFileAttrProcs[index].getProc(interp, index, pathPtr,objPtrRef);
}

/*
 *----------------------------------------------------------------------
 *
 * NativeFileAttrsSet --
 *
 *	This function implements the platform dependent 'file attributes'
 *	subcommand, for the native filesystem, for 'set' operations. This
 *	function is part of Tcl's native filesystem support, and is placed
 *	here because it is shared by Unix and Windows code.
 *
 * Results:
 *	Standard Tcl return code.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
NativeFileAttrsSet(
    Tcl_Interp *interp,		/* The interpreter for error reporting. */
    int index,			/* index of the attribute command. */
    Tcl_Obj *pathPtr,		/* path of file we are operating on. */
    Tcl_Obj *objPtr)		/* set to this value. */
{
    return tclpFileAttrProcs[index].setProc(interp, index, pathPtr, objPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSFileAttrStrings --
 *
 *	This function implements part of the hookable 'file attributes'
 *	subcommand. The appropriate function for the filesystem to which


 *	pathPtr belongs will be called.
 *
 * Results:
 *	The called function may either return an array of strings, or may
 *	instead return NULL and place a Tcl list into the given objPtrRef.
 *	Tcl will take that list and first increment its refCount before using
 *	it. On completion of that use, Tcl will decrement its refCount. Hence
 *	if the list should be disposed of by Tcl when done, it should have a
 *	refCount of zero, and if the list should not be disposed of, the
 *	filesystem should ensure it retains a refCount on the object.

 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

}

/*
 *----------------------------------------------------------------------
 *
 * TclFSFileAttrIndex --
 *
 *	Helper function for converting an attribute name to an index into the
 *	attribute table.
 *
 * Results:
 *	Tcl result code, index written to *indexPtr on result==TCL_OK


 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclFSFileAttrIndex(
    Tcl_Obj *pathPtr,		/* File whose attributes are to be indexed
				 * into. */
    const char *attributeName,	/* The attribute being looked for. */
    int *indexPtr)		/* Where to write the found index. */
{
    Tcl_Obj *listObj = NULL;
    const char *const *attrTable;

    /*
     * Get the attribute table for the file.
     */

}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSFileAttrsGet --
 *
 *	This function implements read access for the hookable 'file

 *	attributes' subcommand. The appropriate function for the filesystem to
 *	which pathPtr belongs will be called.
 *
 * Results:
 *	Standard Tcl return code. The object placed in objPtrRef (if TCL_OK


 *	was returned) is likely to have a refCount of zero. Either way we must
 *	either store it somewhere (e.g. the Tcl result), or Incr/Decr its
 *	refCount to ensure it is properly freed.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSFileAttrsGet(
    Tcl_Interp *interp,		/* The interpreter for error reporting. */
    int index,			/* index of the attribute command. */
    Tcl_Obj *pathPtr,		/* filename we are operating on. */
    Tcl_Obj **objPtrRef)	/* for output. */
{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL && fsPtr->fileAttrsGetProc != NULL) {
	return fsPtr->fileAttrsGetProc(interp, index, pathPtr, objPtrRef);
    }
    Tcl_SetErrno(ENOENT);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSFileAttrsSet --
 *
 *	This function implements write access for the hookable 'file
 *	attributes' subcommand. The appropriate function for the filesystem to


 *	which pathPtr belongs will be called.
 *
 * Results:
 *	Standard Tcl return code.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSFileAttrsSet(
    Tcl_Interp *interp,		/* The interpreter for error reporting. */
    int index,			/* index of the attribute command. */
    Tcl_Obj *pathPtr,		/* filename we are operating on. */
    Tcl_Obj *objPtr)		/* Input value. */
{
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);

    if (fsPtr != NULL && fsPtr->fileAttrsSetProc != NULL) {
	return fsPtr->fileAttrsSetProc(interp, index, pathPtr, objPtr);
    }
    Tcl_SetErrno(ENOENT);
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSGetCwd --
 *
 *	This function replaces the library version of getcwd().
 *
 *	Most VFS's will *not* implement a 'cwdProc'. Tcl now maintains its own
 *	record (in a Tcl_Obj) of the cwd, and an attempt is made to synch this
 *	with the cwd's containing filesystem, if that filesystem provides a
 *	cwdProc (e.g. the native filesystem).
 *
 *	Note that if Tcl's cwd is not in the native filesystem, then of course
 *	Tcl's cwd and the native cwd are different: extensions should
 *	therefore ensure they only access the cwd through this function to
 *	avoid confusion.
 *
 *	If a global cwdPathPtr already exists, it is cached in the thread's
 *	private data structures and reference to the cached copy is returned,
 *	subject to a synchronisation attempt in that cwdPathPtr's fs.
 *
 *	Otherwise, the chain of functions that have been "inserted" into the
 *	filesystem will be called in succession until either a value other
 *	than NULL is returned, or the entire list is visited.
 *
 * Results:
 *	The result is a pointer to a Tcl_Obj specifying the current directory,
 *	or NULL if the current directory could not be determined. If NULL is
 *	returned, an error message is left in the interp's result.
 *
 *	The result already has its refCount incremented for the caller. When
 *	it is no longer needed, that refCount should be decremented.


 *
 * Side effects:
 *	Various objects may be freed and allocated.
 *
 *----------------------------------------------------------------------
 */

Tcl_Obj *
Tcl_FSGetCwd(
    Tcl_Interp *interp)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    if (TclFSCwdPointerEquals(NULL)) {
	FilesystemRecord *fsRecPtr;
	Tcl_Obj *retVal = NULL;

	/*
	 * We've never been called before, try to find a cwd. Call each of the
	 * "Tcl_GetCwd" function in succession. A non-NULL return value
	 * indicates the particular function has succeeded.

	 */

	fsRecPtr = FsGetFirstFilesystem();
	Claim();
	for (; (retVal == NULL) && (fsRecPtr != NULL);
		fsRecPtr = fsRecPtr->nextPtr) {
	    ClientData retCd;

	    proc2 = (TclFSGetCwdProc2 *) fsRecPtr->fsPtr->getCwdProc;
	    retCd = proc2(NULL);
	    if (retCd != NULL) {
		Tcl_Obj *norm;

		/*
		 * Looks like a new current directory.
		 */

		retVal = fsRecPtr->fsPtr->internalToNormalizedProc(retCd);
		Tcl_IncrRefCount(retVal);
		norm = TclFSNormalizeAbsolutePath(interp,retVal);
		if (norm != NULL) {
		    /*
		     * We found a cwd, which is now in our global storage. We
		     * must make a copy. Norm already has a refCount of 1.
		     *
		     * Threading issue: note that multiple threads at system
		     * startup could in principle call this function
		     * simultaneously. They will therefore each set the
		     * cwdPathPtr independently. That behaviour is a bit
		     * peculiar, but should be fine. Once we have a cwd, we'll

		     * always be in the 'else' branch below which is simpler.

		     */

		    FsUpdateCwd(norm, retCd);
		    Tcl_DecrRefCount(norm);
		} else {
		    fsRecPtr->fsPtr->freeInternalRepProc(retCd);
		}
		Tcl_DecrRefCount(retVal);
		retVal = NULL;
		Disclaim();
		goto cdDidNotChange;
	    } else if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"error getting working directory name: %s",
			Tcl_PosixError(interp)));
	    }
	}
	Disclaim();


	/*
	 * Now the 'cwd' may NOT be normalized, at least on some platforms.

	 * For the sake of efficiency, we want a completely normalized cwd at
	 * all times.
	 *
	 * Finally, if retVal is NULL, we do not have a cwd, which could be
	 * problematic.
	 */

	if (retVal != NULL) {
	    Tcl_Obj *norm = TclFSNormalizeAbsolutePath(interp, retVal);

	    if (norm != NULL) {
		/*
		 * We found a cwd, which is now in our global storage. We must
		 * make a copy. Norm already has a refCount of 1.

		 *
		 * Threading issue: note that multiple threads at system
		 * startup could in principle call this function
		 * simultaneously. They will therefore each set the cwdPathPtr
		 * independently. That behaviour is a bit peculiar, but should
		 * be fine. Once we have a cwd, we'll always be in the 'else'
		 * branch below which is simpler.
		 */

		ClientData cd = (ClientData) Tcl_FSGetNativePath(norm);

		FsUpdateCwd(norm, TclNativeDupInternalRep(cd));
		Tcl_DecrRefCount(norm);
	    }
	    Tcl_DecrRefCount(retVal);





	}
    } else {
	/*
	 * We already have a cwd cached, but we want to give the filesystem it
	 * is in a chance to check whether that cwd has changed, or is perhaps
	 * no longer accessible. This allows an error to be thrown if, say,
	 * the permissions on that directory have changed.

	 */

	const Tcl_Filesystem *fsPtr =
		Tcl_FSGetFileSystemForPath(tsdPtr->cwdPathPtr);
	ClientData retCd = NULL;
	Tcl_Obj *retVal, *norm;


	/*
	 * If the filesystem couldn't be found, or if no cwd function exists
	 * for this filesystem, then we simply assume the cached cwd is ok.
	 * If we do call a cwd, we must watch for errors (if the cwd returns
	 * NULL). This ensures that, say, on Unix if the permissions of the
	 * cwd change, 'pwd' does actually throw the correct error in Tcl.
	 * (This is tested for in the test suite on unix).
	 */

	if (fsPtr == NULL || fsPtr->getCwdProc == NULL) {
	    goto cdDidNotChange;
	}

	if (fsPtr->version == TCL_FILESYSTEM_VERSION_1) {
	    retVal = fsPtr->getCwdProc(interp);
	} else {
	    /*

	     * Looks like a new current directory.
	     */

	    retVal = fsPtr->internalToNormalizedProc(retCd);
	    Tcl_IncrRefCount(retVal);
	}


	/*
	 * Check if the 'cwd' function returned an error; if so, reset the


	 * cwd.
	 */

	if (retVal == NULL) {
	    FsUpdateCwd(NULL, NULL);
	    goto cdDidNotChange;
	}

	/*
	 * Normalize the path.
	 */

	norm = TclFSNormalizeAbsolutePath(interp, retVal);


	/*
	 * Check whether cwd has changed from the value previously stored in
	 * cwdPathPtr. Really 'norm' shouldn't be NULL, but we are careful.
	 */

	if (norm == NULL) {
	    /* Do nothing */
	    if (retCd != NULL) {
		fsPtr->freeInternalRepProc(retCd);
	    }
	} else if (norm == tsdPtr->cwdPathPtr) {
	    goto cdEqual;
	} else {
	    /*

	     * Note that both 'norm' and 'tsdPtr->cwdPathPtr' are normalized
	     * paths. Therefore we can be more efficient than calling
	     * 'Tcl_FSEqualPaths', and in addition avoid a nasty infinite loop
	     * bug when trying to normalize tsdPtr->cwdPathPtr.
	     */

	    size_t len1, len2;
	    const char *str1, *str2;

	    str1 = TclGetStringFromObj(tsdPtr->cwdPathPtr, &len1);
	    str2 = TclGetStringFromObj(norm, &len2);
	    if ((len1 == len2) && (strcmp(str1, str2) == 0)) {
		/*
		 * If the paths were equal, we can be more efficient and
		 * retain the old path object which will probably already be
		 * shared. In this case we can simply free the normalized path
		 * we just calculated.
		 */

	    cdEqual:
		Tcl_DecrRefCount(norm);
		if (retCd != NULL) {
		    fsPtr->freeInternalRepProc(retCd);
		}
	    } else {




		FsUpdateCwd(norm, retCd);
		Tcl_DecrRefCount(norm);
	    }
	}
	Tcl_DecrRefCount(retVal);
    }

  cdDidNotChange:
    if (tsdPtr->cwdPathPtr != NULL) {
	Tcl_IncrRefCount(tsdPtr->cwdPathPtr);
    }

    return tsdPtr->cwdPathPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSChdir --
 *
 *	This function replaces the library version of chdir().
 *
 *	The path is normalized and then passed to the filesystem which claims
 *	it.
 *
 * Results:
 *	See chdir() documentation. If successful, we keep a record of the
 *	successful path in cwdPathPtr for subsequent calls to getcwd.
 *
 * Side effects:
 *	See chdir() documentation. The global cwdPathPtr may change value.



 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSChdir(
    Tcl_Obj *pathPtr)

	return retVal;
    }

    fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);
    if (fsPtr != NULL) {
	if (fsPtr->chdirProc != NULL) {
	    /*
	     * If this fails, an appropriate errno will have been stored using
	     * 'Tcl_SetErrno()'.
	     */

	    retVal = fsPtr->chdirProc(pathPtr);
	} else {
	    /*
	     * Fallback on stat-based implementation.
	     */

	    Tcl_StatBuf buf;

	    /*
	     * If the file can be stat'ed and is a directory and is readable,
	     * then we can chdir. If any of these actions fail, then
	     * 'Tcl_SetErrno()' should automatically have been called to set
	     * an appropriate error code.
	     */

	    if ((Tcl_FSStat(pathPtr, &buf) == 0) && (S_ISDIR(buf.st_mode))
		    && (Tcl_FSAccess(pathPtr, R_OK) == 0)) {
		/*
		 * We allow the chdir.

		 */

		retVal = 0;




	    }
	}
    } else {
	Tcl_SetErrno(ENOENT);
    }


    /*
     * The cwd changed, or an error was thrown. If an error was thrown, we can
     * just continue (and that will report the error to the user). If there
     * was no error we must assume that the cwd was actually changed to the
     * normalized value we calculated above, and we must therefore cache that
     * information.
     *
     * If the filesystem in question has a getCwdProc, then the correct logic
     * which performs the part below is already part of the Tcl_FSGetCwd()
     * call, so no need to replicate it again. This will have a side effect
     * though. The private authoritative representation of the current working
     * directory stored in cwdPathPtr in static memory will be out-of-sync
     * with the real OS-maintained value. The first call to Tcl_FSGetCwd will
     * however recalculate the private copy to match the OS-value so
     * everything will work right.
     *
     * However, if there is no getCwdProc, then we _must_ update our private
     * storage of the cwd, since this is the only opportunity to do that!
     *
     * Note: We currently call this block of code irrespective of whether
     * there was a getCwdProc or not, but the code should all in principle
     * work if we only call this block if fsPtr->getCwdProc == NULL.
     */

    if (retVal == 0) {
	/*
	 * Note that this normalized path may be different to what we found
	 * above (or at least a different object), if the filesystem epoch

	 * changed recently. This can actually happen with scripted documents
	 * very easily. Therefore we ask for the normalized path again (the
	 * correct value will have been cached as a result of the
	 * Tcl_FSGetFileSystemForPath call above anyway).
	 */

	Tcl_Obj *normDirName = Tcl_FSGetNormalizedPath(NULL, pathPtr);

	if (normDirName == NULL) {
	    /* Not really true, but what else to do? */
	    Tcl_SetErrno(ENOENT);
	    return -1;
	}

	if (fsPtr == &tclNativeFilesystem) {
	    /*
	     * For the native filesystem, we keep a cache of the native
	     * representation of the cwd. But, we want to do that for the
	     * exact format that is returned by 'getcwd' (so that we can later
	     * compare the two representations for equality), which might not
	     * be exactly the same char-string as the native representation of
	     * the fully normalized path (e.g. on Windows there's a
	     * forward-slash vs backslash difference). Hence we ask for this
	     * again here. On Unix it might actually be true that we always
	     * have the correct form in the native rep in which case we could
	     * simply use:
	     *		cd = Tcl_FSGetNativePath(pathPtr);
	     * instead. This should be examined by someone on Unix.
	     */

	    ClientData cd;
	    ClientData oldcd = tsdPtr->cwdClientData;

	    /*

	     * Assumption we are using a filesystem version 2.
	     */

	    TclFSGetCwdProc2 *proc2 = (TclFSGetCwdProc2 *) fsPtr->getCwdProc;

	    cd = proc2(oldcd);
	    if (cd != oldcd) {














		FsUpdateCwd(normDirName, cd);
	    }
	} else {









	    FsUpdateCwd(normDirName, NULL);
	}


	/*
	 * If the filesystem changed between old and new cwd

	 * force filesystem refresh on path objects.
	 */
	if (oldFsPtr != NULL && fsPtr != oldFsPtr) {
	    Tcl_FSMountsChanged(NULL);
	}





    }

    return retVal;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FSLoadFile --
 *
 *	Dynamically loads a binary code file into memory and returns the
 *	addresses of two functions within that file, if they are defined. The
 *	appropriate function for the filesystem to which pathPtr belongs will
 *	be called.
 *
 *	Note that the native filesystem doesn't actually assume 'pathPtr' is a
 *	path. Rather it assumes pathPtr is either a path or just the name
 *	(tail) of a file which can be found somewhere in the environment's
 *	loadable path. This behaviour is not very compatible with virtual
 *	filesystems (and has other problems documented in the load man-page),
 *	so it is advised that full paths are always used.
 *
 * Results:
 *	A standard Tcl completion code. If an error occurs, an error message
 *	is left in the interp's result.
 *
 * Side effects:
 *	New code suddenly appears in memory. This may later be unloaded by
 *	passing the clientData to the unloadProc.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_FSLoadFile(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Obj *pathPtr,		/* Name of the file containing the desired
				 * code. */
    const char *sym1, const char *sym2,
				/* Names of two functions to look up in the
				 * file's symbol table. */
    Tcl_PackageInitProc **proc1Ptr, Tcl_PackageInitProc **proc2Ptr,
				/* Where to return the addresses corresponding
				 * to sym1 and sym2. */
    Tcl_LoadHandle *handlePtr,	/* Filled with token for dynamically loaded
				 * file which will be passed back to
				 * (*unloadProcPtr)() to unload the file. */
    Tcl_FSUnloadFileProc **unloadProcPtr)
				/* Filled with address of Tcl_FSUnloadFileProc
				 * function which should be used for this
				 * file. */
{
    const char *symbols[3];
    void *procPtrs[2];
    int res;

    /*
     * Initialize the arrays.
     */

    symbols[0] = sym1;
    symbols[1] = sym2;
    symbols[2] = NULL;

    /*
     * Perform the load.
     */

    res = Tcl_LoadFile(interp, pathPtr, symbols, 0, procPtrs, handlePtr);
    if (res == TCL_OK) {
	*proc1Ptr = (Tcl_PackageInitProc *) procPtrs[0];
	*proc2Ptr = (Tcl_PackageInitProc *) procPtrs[1];
    } else {
	*proc1Ptr = *proc2Ptr = NULL;
    }

    return res;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_LoadFile --
 *
 *	Dynamically loads a binary code file into memory and returns the
 *	addresses of a number of given functions within that file, if they are
 *	defined. The appropriate function for the filesystem to which pathPtr
 *	belongs will be called.
 *

 *	Note that the native filesystem doesn't actually assume 'pathPtr' is a
 *	path. Rather it assumes pathPtr is either a path or just the name
 *	(tail) of a file which can be found somewhere in the environment's
 *	loadable path. This behaviour is not very compatible with virtual
 *	filesystems (and has other problems documented in the load man-page),
 *	so it is advised that full paths are always used.

 *
 * Results:
 *	A standard Tcl completion code. If an error occurs, an error message
 *	is left in the interp's result.
 *
 * Side effects:
 *	New code suddenly appears in memory. This may later be unloaded by
 *	calling TclFS_UnloadFile.
 *
 *----------------------------------------------------------------------
 */

/*
 * Workaround for issue with modern HPUX which do allow the unlink (no ETXTBSY
 * error) yet somehow trash some internal data structures which prevents the
 * second and further shared libraries from getting properly loaded. Only the
 * first is ok. We try to get around the issue by not unlinking, i.e.,
 * emulating the behaviour of the older HPUX which denied removal.
 *
 * Doing the unlink is also an issue within docker containers, whose AUFS
 * bungles this as well, see
 *     https://github.com/dotcloud/docker/issues/1911
 *
 * For these situations the change below makes the execution of the unlink
 * semi-controllable at runtime.
 *
 *     An AUFS filesystem (if it can be detected) will force avoidance of
 *     unlink. The env variable TCL_TEMPLOAD_NO_UNLINK allows detection of a
 *     users general request (unlink and not.
 *
 * By default the unlink is done (if not in AUFS). However if the variable is
 * present and set to true (any integer > 0) then the unlink is skipped.
 */

static int
skipUnlink(
    Tcl_Obj *shlibFile)
{
    /*
     * Order of testing:
     * 1. On hpux we generally want to skip unlink in general
     *
     * Outside of hpux then:

     * 2. For a general user request   (TCL_TEMPLOAD_NO_UNLINK present,
     *					non-empty, => int)
     * 3. For general AUFS environment (statfs, if available).
     *
     * Ad 2: This variable can disable/override the AUFS detection, i.e. for
     *	     testing if a newer AUFS does not have the bug any more.

     *
     * Ad 3: This is conditionally compiled in. Condition currently must be
     *	     set manually. This part needs proper tests in the configure(.in).
     */


#ifdef hpux
    return 1;
#else
    char *skipstr = getenv("TCL_TEMPLOAD_NO_UNLINK");

    if (skipstr && (skipstr[0] != '\0')) {
	return atoi(skipstr);
    }

#ifdef TCL_TEMPLOAD_NO_UNLINK



#ifndef NO_FSTATFS
    {
	struct statfs fs;
	/*
	 * Have fstatfs. May not have the AUFS super magic ... Indeed our build
	 * box is too old to have it directly in the headers. Define taken from
	 *     http://mooon.googlecode.com/svn/trunk/linux_include/linux/aufs_type.h
	 *     http://aufs.sourceforge.net/
	 * Better reference will be gladly taken.
	 */
#ifndef AUFS_SUPER_MAGIC



#define AUFS_SUPER_MAGIC ('a' << 24 | 'u' << 16 | 'f' << 8 | 's')
#endif /* AUFS_SUPER_MAGIC */
	if ((statfs(TclGetString(shlibFile), &fs) == 0)
		&& (fs.f_type == AUFS_SUPER_MAGIC)) {
	    return 1;
	}
    }
#endif /* ... NO_FSTATFS */
#endif /* ... TCL_TEMPLOAD_NO_UNLINK */

    /*
     * Fallback: !hpux, no EV override, no AUFS (detection, nor detected):
     * Don't skip
     */
    return 0;
#endif /* hpux */
}

int
Tcl_LoadFile(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Obj *pathPtr,		/* Name of the file containing the desired
				 * code. */
    const char *const symbols[],/* Names of functions to look up in the file's
				 * symbol table. */
    int flags,			/* Flags */
    void *procVPtrs,		/* Where to return the addresses corresponding
				 * to symbols[]. */
    Tcl_LoadHandle *handlePtr)	/* Filled with token for shared library
				 * information which can be used in
				 * TclpFindSymbol. */
{
    void **procPtrs = (void **) procVPtrs;
    const Tcl_Filesystem *fsPtr = Tcl_FSGetFileSystemForPath(pathPtr);
    const Tcl_Filesystem *copyFsPtr;
    Tcl_FSUnloadFileProc *unloadProcPtr;
    Tcl_Obj *copyToPtr;
    Tcl_LoadHandle newLoadHandle = NULL;

	}
	if (Tcl_GetErrno() != EXDEV) {
	    return retVal;
	}
    }

    /*
     * The filesystem doesn't support 'load', so we fall back on the following
     * technique:
     *
     * First check if it is readable -- and exists!


     */

    if (Tcl_FSAccess(pathPtr, R_OK) != 0) {
	if (interp) {
	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		    "couldn't load library \"%s\": %s",
		    TclGetString(pathPtr), Tcl_PosixError(interp)));
	}
	return TCL_ERROR;
    }

#ifdef TCL_LOAD_FROM_MEMORY
    /*
     * The platform supports loading code from memory, so ask for a buffer of
     * the appropriate size, read the file into it and load the code from the
     * buffer:
     */

    {
	int ret, size;
	void *buffer;
	Tcl_StatBuf statBuf;
	Tcl_Channel data;

	ret = Tcl_FSStat(pathPtr, &statBuf);
	if (ret < 0) {
	    goto mustCopyToTempAnyway;
	}
	size = (int) statBuf.st_size;

	/*
	 * Tcl_Read takes an int: check that file size isn't wide.
	 */

	if (size != (Tcl_WideInt) statBuf.st_size) {
	    goto mustCopyToTempAnyway;
	}
	data = Tcl_FSOpenFileChannel(interp, pathPtr, "rb", 0666);
	if (!data) {