* malloced and has this many total entries
				 * allocated to it (not all may be in use at
				 * once). Zero means that the environment
				 * array is in its original static state. */
#endif
} env;

#if defined(_WIN32) && (defined(_UNICODE) || defined(UNICODE))
#  define tenviron _wenviron
#  define tenviron2utfdstr(tenvstr, len, dstr) \
		Tcl_WinTCharToUtf((TCHAR *)tenvstr, len, dstr)
#  define utf2tenvirondstr(str, len, dstr) \
		(const char *)Tcl_WinUtfToTChar(str, len, dstr)
#  define techar TCHAR
#  ifdef USE_PUTENV
#    define putenv(env) _wputenv((const wchar_t *)env)
#  endif
#else 
#  define tenviron environ
#  define tenviron2utfdstr(tenvstr, len, dstr) \
		Tcl_ExternalToUtfDString(NULL, tenvstr, len, dstr)
#  define utf2tenvirondstr(str, len, dstr) \
		Tcl_UtfToExternalDString(NULL, str, len, dstr)
#  define techar char
#endif

#define tNTL sizeof(techar)

/*
 * Declarations for local functions defined in this file:
 */

static char *		EnvTraceProc(ClientData clientData, Tcl_Interp *interp,
			    const char *name1, const char *name2, int flags);
static void		ReplaceString(const char *oldStr, char *newStr);

    /*
     * Go through the environment array and transfer its values into Tcl. At
     * the same time, remove those elements we add/update from the hash table
     * of existing elements, so that after this part processes, that table
     * will hold just the parts to remove.
     */

    if (tenviron[0] != NULL) {
	int i;

	Tcl_MutexLock(&envMutex);
	for (i = 0; tenviron[i] != NULL; i++) {
	    Tcl_Obj *obj1, *obj2;
	    const char *p1;
	    char *p2;

	    p1 = tenviron2utfdstr(tenviron[i], -1, &envString);
	    p2 = strchr(p1, '=');
	    if (p2 == NULL) {
		/*
		 * This condition seem to happen occasionally under some
		 * versions of Solaris, or when encoding accidents swallow the
		 * '='; ignore the entry.
		 */

#ifndef USE_PUTENV
	/*
	 * We need to handle the case where the environment may be changed
	 * outside our control. ourEnvironSize is only valid if the current
	 * environment is the one we allocated. [Bug 979640]
	 */

	if ((env.ourEnviron != (char *)tenviron) || (length+2 > env.ourEnvironSize)) {
	    char **newEnviron = ckalloc((length + 5) * sizeof(char *));

	    memcpy(newEnviron, tenviron, length * sizeof(char *));
	    if ((env.ourEnvironSize != 0) && (env.ourEnviron != NULL)) {
		ckfree(env.ourEnviron);
	    }
	    tenviron = (techar **)(env.ourEnviron = newEnviron);
	    env.ourEnvironSize = length + 5;
	}
	index = length;
	tenviron[index + 1] = NULL;
#endif /* USE_PUTENV */
	oldValue = NULL;
	nameLength = strlen(name);
    } else {
	const char *oldEnv;

	/*
	 * Compare the new value to the existing value. If they're the same
	 * then quit immediately (e.g. don't rewrite the value or propagate it
	 * to other interpreters). Otherwise, when there are N interpreters
	 * there will be N! propagations of the same value among the
	 * interpreters.
	 */

	oldEnv = tenviron2utfdstr(tenviron[index], -1, &envString);
	if (strcmp(value, oldEnv + (length + 1)) == 0) {
	    Tcl_DStringFree(&envString);
	    Tcl_MutexUnlock(&envMutex);
	    return;
	}
	Tcl_DStringFree(&envString);

	oldValue = (char *)tenviron[index];
	nameLength = (unsigned) length;
    }

    /*
     * Create a new entry. Build a complete UTF string that contains a
     * "name=value" pattern. Then convert the string to the native encoding,
     * and set the environ array value.
     */

    valueLength = strlen(value);
    p = ckalloc(nameLength + valueLength + 2);
    memcpy(p, name, nameLength);
    p[nameLength] = '=';
    memcpy(p+nameLength+1, value, valueLength+1);
    p2 = utf2tenvirondstr(p, -1, &envString);

    /*
     * Copy the native string to heap memory.
     */

    p = ckrealloc(p, Tcl_DStringLength(&envString) + tNTL);
    memcpy(p, p2, (unsigned) Tcl_DStringLength(&envString) + tNTL);
    Tcl_DStringFree(&envString);

#ifdef USE_PUTENV
    /*
     * Update the system environment.
     */

    putenv(p);
    index = TclpFindVariable(name, &length);
#else
    tenviron[index] = (techar *)p;
#endif /* USE_PUTENV */

    /*
     * Watch out for versions of putenv that copy the string (e.g. VC++). In
     * this case we need to free the string immediately. Otherwise update the
     * string in the cache.
     */

    if ((index != -1) && (tenviron[index] == (techar *)p)) {
	ReplaceString(oldValue, p);
#ifdef HAVE_PUTENV_THAT_COPIES
    } else {
	/*
	 * This putenv() copies instead of taking ownership.
	 */

    }

    /*
     * First convert the native string to UTF. Then separate the string into
     * name and value parts, and call TclSetEnv to do all of the real work.
     */

    name = tenviron2utfdstr(assignment, -1, &nameString);
    value = strchr(name, '=');

    if ((value != NULL) && (value != name)) {
	value[0] = '\0';
	TclSetEnv(name, value+1);
    }

	return;
    }

    /*
     * Remember the old value so we can free it if Tcl created the string.
     */

    oldValue = (char *)tenviron[index];

    /*
     * Update the system environment. This must be done before we update the
     * interpreters or we will recurse.
     */

#ifdef USE_PUTENV_FOR_UNSET

    string[length+1] = '\0';
#else
    string = ckalloc(length + 1);
    memcpy(string, name, (size_t) length);
    string[length] = '\0';
#endif /* _WIN32 */

    utf2tenvirondstr(string, -1, &envString);
    string = ckrealloc(string, Tcl_DStringLength(&envString) + tNTL);
    memcpy(string, Tcl_DStringValue(&envString),
	    (unsigned) Tcl_DStringLength(&envString) + tNTL);
    Tcl_DStringFree(&envString);

    putenv(string);

    /*
     * Watch out for versions of putenv that copy the string (e.g. VC++). In
     * this case we need to free the string immediately. Otherwise update the
     * string in the cache.
     */

    if (tenviron[index] == (techar *)string) {
	ReplaceString(oldValue, string);
#ifdef HAVE_PUTENV_THAT_COPIES
    } else {
	/*
	 * This putenv() copies instead of taking ownership.
	 */

	ckfree(string);
#endif /* HAVE_PUTENV_THAT_COPIES */
    }
#else /* !USE_PUTENV_FOR_UNSET */
    for (envPtr = (char *)(tenviron+index+1); ; envPtr++) {
	envPtr[-1] = *envPtr;
	if (*envPtr == NULL) {
	    break;
	}
    }
    ReplaceString(oldValue, NULL);
#endif /* USE_PUTENV_FOR_UNSET */

    Tcl_MutexLock(&envMutex);
    index = TclpFindVariable(name, &length);
    result = NULL;
    if (index != -1) {
	Tcl_DString envStr;

	result = tenviron2utfdstr(tenviron[index], -1, &envStr);
	result += length;
	if (*result == '=') {
	    result++;
	    Tcl_DStringInit(valuePtr);
	    Tcl_DStringAppend(valuePtr, result, -1);
	    result = Tcl_DStringValue(valuePtr);
	} else {

.SUFFIXES: .${OBJEXT}
.SUFFIXES: .$(RES)
.SUFFIXES: .rc

# Special case object targets

tclEnv.${OBJEXT}: tclEnv.c
	$(CC) -c $(CC_SWITCHES) -DBUILD_tcl $(EXTFLAGS) -DUNICODE -D_UNICODE @DEPARG@ $(CC_OBJNAME)

tclTestMain.${OBJEXT}: tclAppInit.c
	$(CC) -c $(CC_SWITCHES) -DTCL_TEST -DUNICODE -D_UNICODE $(EXTFLAGS) @DEPARG@ $(CC_OBJNAME)

tclWinInit.${OBJEXT}: tclWinInit.c
	$(CC) -c $(CC_SWITCHES) -DBUILD_tcl $(EXTFLAGS) -DUNICODE -D_UNICODE @DEPARG@ $(CC_OBJNAME)

tclWinPipe.${OBJEXT}: tclWinPipe.c
	$(CC) -c $(CC_SWITCHES) -DBUILD_tcl $(EXTFLAGS) @DEPARG@ $(CC_OBJNAME)

tclWinReg.${OBJEXT}: tclWinReg.c
	$(CC) -c $(CC_SWITCHES) $(EXTFLAGS) @DEPARG@ $(CC_OBJNAME)

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

#if defined(_WIN32) && (defined(_UNICODE) || defined(UNICODE))
#  define tenviron _wenviron
#  define tenviron2utfdstr(tenvstr, len, dstr) \
		Tcl_WinTCharToUtf((TCHAR *)tenvstr, len, dstr)
#else 
#  define tenviron environ
#  define tenviron2utfdstr(tenvstr, len, dstr) \
		Tcl_ExternalToUtfDString(NULL, tenvstr, len, dstr)
#endif

int
TclpFindVariable(
    const char *name,		/* Name of desired environment variable
				 * (UTF-8). */
    int *lengthPtr)		/* Used to return length of name (for
				 * successful searches) or number of non-NULL
				 * entries in environ (for unsuccessful

    length = strlen(name);
    nameUpper = ckalloc(length + 1);
    memcpy(nameUpper, name, (size_t) length+1);
    Tcl_UtfToUpper(nameUpper);

    Tcl_DStringInit(&envString);
    for (i = 0, env = (const char *)tenviron[i];
	env != NULL;
	i++, env = (const char *)tenviron[i]) {
	/*
	 * Chop the env string off after the equal sign, then Convert the name
	 * to all upper case, so we do not have to convert all the characters
	 * after the equal sign.
	 */

	envUpper = tenviron2utfdstr(env, -1, &envString);
	p1 = strchr(envUpper, '=');
	if (p1 == NULL) {
	    continue;
	}
	length = (int) (p1 - envUpper);
	Tcl_DStringSetLength(&envString, length+1);
	Tcl_UtfToUpper(envUpper);