Index: doc/FileSystem.3
==================================================================
--- doc/FileSystem.3
+++ doc/FileSystem.3
@@ -412,11 +412,11 @@
 .PP
 \fBTcl_FSEvalFileEx\fR reads the file given by \fIpathPtr\fR using
 the encoding identified by \fIencodingName\fR and evaluates
 its contents as a Tcl script. It returns the same information as
 \fBTcl_EvalObjEx\fR.
-If \fIencodingName\fR is NULL, the system encoding is used for
+If \fIencodingName\fR is NULL, the utf-8 encoding is used for
 reading the file contents.
 If the file could not be read then a Tcl error is returned to describe
 why the file could not be read.
 The eofchar for files is
 .QW \e32
@@ -428,11 +428,11 @@
 or
 .QW \eu001a ,
 which will be safely substituted by the Tcl interpreter into
 .QW ^Z .
 \fBTcl_FSEvalFile\fR is a simpler version of
-\fBTcl_FSEvalFileEx\fR that always uses the system encoding
+\fBTcl_FSEvalFileEx\fR that always uses the utf-8 encoding
 when reading the file.
 .PP
 \fBTcl_FSLoadFile\fR dynamically loads a binary code file into memory and
 returns the addresses of two procedures within that file, if they are
 defined. The appropriate function for the filesystem to which \fIpathPtr\fR

Index: doc/InitSubSyst.3
==================================================================
--- doc/InitSubSyst.3
+++ doc/InitSubSyst.3
@@ -21,11 +21,11 @@
 library. This procedure is typically invoked as the very
 first thing in the application's main program.
 .PP
 \fBTcl_InitSubsystems\fR is very similar in use to
 \fBTcl_FindExecutable\fR. It can be used when Tcl is
-used as utility library, no other encodings than utf8,
+used as utility library, no other encodings than utf-8,
 iso8859-1 or unicode are used, and no interest exists in the
 value of \fBinfo nameofexecutable\fR. The system encoding will not
-be extracted from the environment, but falls back to iso8859-1.
+be extracted from the environment, but falls back to utf-8.
 .SH KEYWORDS
 binary, executable file

Index: doc/source.n
==================================================================
--- doc/source.n
+++ doc/source.n
@@ -45,11 +45,11 @@
 .PP
 A leading BOM (Byte order mark) contained in the file is ignored for unicode encodings (utf-8, utf-16, ucs-2).
 .PP
 The \fB\-encoding\fR option is used to specify the encoding of
 the data stored in \fIfileName\fR.  When the \fB\-encoding\fR option
-is omitted, the system encoding is assumed.
+is omitted, the utf-8 encoding is assumed.
 .SH EXAMPLE
 .PP
 Run the script in the file \fBfoo.tcl\fR and then the script in the
 file \fBbar.tcl\fR:
 .PP

Index: generic/tclIOUtil.c
==================================================================
--- generic/tclIOUtil.c
+++ generic/tclIOUtil.c
@@ -1682,11 +1682,11 @@
     Tcl_Interp *interp,		/* Interpreter that evaluates the script. */
     Tcl_Obj *pathPtr,		/* Pathname of the file to process.
 				 * Tilde-substitution is performed on this
 				 * pathname. */
     const char *encodingName)	/* Either the name of an encoding or NULL to
-				   use the system encoding. */
+				   use the utf-8 encoding. */
 {
     size_t length;
 	int result = TCL_ERROR;
     Tcl_StatBuf statBuf;
     Tcl_Obj *oldScriptFile;
@@ -1721,20 +1721,20 @@
 
     Tcl_SetChannelOption(interp, chan, "-eofchar", "\32 {}");
 
     /*
      * If the encoding is specified, set the channel to that encoding.
-     * Otherwise don't touch it, leaving things up to the system encoding.  If
-     * the encoding is unknown report an error.
+     * Otherwise use utf-8.  If the encoding is unknown report an error.
      */
 
-    if (encodingName != NULL) {
-	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
-		!= TCL_OK) {
-	    Tcl_CloseEx(interp,chan,0);
-	    return result;
-	}
+    if (encodingName == NULL) {
+	encodingName = "utf-8";
+    }
+    if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
+	    != TCL_OK) {
+	Tcl_CloseEx(interp,chan,0);
+	return result;
     }
 
     TclNewObj(objPtr);
     Tcl_IncrRefCount(objPtr);
 
@@ -1820,11 +1820,11 @@
     Tcl_Interp *interp,		/* Interpreter in which to evaluate the script. */
     Tcl_Obj *pathPtr,		/* Pathname of a file containing the script to
 				 * evaluate. Tilde-substitution is performed on
 				 * this pathname. */
     const char *encodingName)	/* The name of an encoding to use, or NULL to
-				 *  use the system encoding. */
+				 *  use the utf-8 encoding. */
 {
     Tcl_StatBuf statBuf;
     Tcl_Obj *oldScriptFile, *objPtr;
     Interp *iPtr;
     Tcl_Channel chan;
@@ -1857,20 +1857,20 @@
 
     Tcl_SetChannelOption(interp, chan, "-eofchar", "\32 {}");
 
     /*
      * If the encoding is specified, set the channel to that encoding.
-     * Otherwise don't touch it, leaving things up to the system encoding.  If
-     * the encoding is unknown report an error.
+     * Otherwise use utf-8.  If the encoding is unknown report an error.
      */
 
-    if (encodingName != NULL) {
-	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
-		!= TCL_OK) {
-	    Tcl_CloseEx(interp, chan, 0);
-	    return TCL_ERROR;
-	}
+    if (encodingName == NULL) {
+	encodingName = "utf-8";
+    }
+    if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
+	    != TCL_OK) {
+	Tcl_CloseEx(interp, chan, 0);
+	return TCL_ERROR;
     }
 
     TclNewObj(objPtr);
     Tcl_IncrRefCount(objPtr);
 

Index: library/auto.tcl
==================================================================
--- library/auto.tcl
+++ library/auto.tcl
@@ -263,11 +263,11 @@
 	}
     }
     auto_mkindex_parser::cleanup
 
     set fid [open "tclIndex" w]
-    fconfigure $fid -translation lf
+    fconfigure $fid -encoding utf-8 -translation lf
     puts -nonewline $fid $index
     close $fid
     cd $oldDir
 }
 
@@ -290,11 +290,11 @@
     }
     foreach file [lsort [glob -- {*}$args]] {
 	set f ""
 	set error [catch {
 	    set f [open $file]
-	    fconfigure $f -eofchar \032
+	    fconfigure $f -encoding utf-8 -eofchar \032
 	    while {[gets $f line] >= 0} {
 		if {[regexp {^proc[ 	]+([^ 	]*)} $line match procName]} {
 		    set procName [lindex [auto_qualify $procName "::"] 0]
 		    append index "set [list auto_index($procName)]"
 		    append index " \[list source \[file join \$dir [list $file]\]\]\n"
@@ -309,11 +309,11 @@
 	}
     }
     set f ""
     set error [catch {
 	set f [open tclIndex w]
-	fconfigure $f -translation lf
+	fconfigure $f -encoding utf-8 -translation lf
 	puts -nonewline $f $index
 	close $f
 	cd $oldDir
     } msg opts]
     if {$error} {
@@ -402,11 +402,11 @@
     variable imports
 
     set scriptFile $file
 
     set fid [open $file]
-    fconfigure $fid -eofchar \032
+    fconfigure $fid -encoding utf-8 -eofchar \032
     set contents [read $fid]
     close $fid
 
     # There is one problem with sourcing files into the safe interpreter:
     # references like "$x" will fail since code is not really being executed

Index: library/clock.tcl
==================================================================
--- library/clock.tcl
+++ library/clock.tcl
@@ -3312,11 +3312,11 @@
 	return -code error \
 	    -errorcode [list CLOCK badTimeZone $:fileName] \
 	    "time zone \":$fileName\" not valid"
     }
     try {
-	source -encoding utf-8 [file join $DataDir $fileName]
+	source [file join $DataDir $fileName]
     } on error {} {
 	return -code error \
 	    -errorcode [list CLOCK badTimeZone :$fileName] \
 	    "time zone \":$fileName\" not found"
     }

Index: library/init.tcl
==================================================================
--- library/init.tcl
+++ library/init.tcl
@@ -110,11 +110,11 @@
 	# Auto-loading stubs for 'clock.tcl'
 
 	foreach cmd {add format scan} {
 	    proc ::tcl::clock::$cmd args {
 		variable TclLibDir
-		source -encoding utf-8 [file join $TclLibDir clock.tcl]
+		source [file join $TclLibDir clock.tcl]
 		return [uplevel 1 [info level 0]]
 	    }
 	}
 
 	rename ::tcl::initClock {}

Index: library/install.tcl
==================================================================
--- library/install.tcl
+++ library/install.tcl
@@ -33,11 +33,11 @@
       set version [lindex [split $fname -] 1]
       ###
       # Read the file, and override assumptions as needed
       ###
       set fin [open $file r]
-      fconfigure $fin -eofchar \032
+      fconfigure $fin -encoding utf-8 -eofchar \032
       set dat [read $fin]
       close $fin
       # Look for a teapot style Package statement
       foreach line [split $dat \n] {
         set line [string trim $line]
@@ -57,11 +57,11 @@
       append buffer "package ifneeded $package $version \[list source \[file join \$dir [file tail $file]\]\]" \n
     }
     foreach file [glob -nocomplain $path/*.tcl] {
       if { [file tail $file] == "version_info.tcl" } continue
       set fin [open $file r]
-      fconfigure $fin -eofchar \032
+      fconfigure $fin -encoding utf-8 -eofchar \032
       set dat [read $fin]
       close $fin
       if {![regexp "package provide" $dat]} continue
       set fname [file rootname [file tail $file]]
       # Look for a package provide statement
@@ -77,11 +77,11 @@
       }
     }
     return $buffer
   }
   set fin [open $pkgidxfile r]
-  fconfigure $fin -eofchar \032
+  fconfigure $fin -encoding utf-8 -eofchar \032
   set dat [read $fin]
   close $fin
   set trace 0
   #if {[file tail $path] eq "tool"} {
   #  set trace 1

Index: library/package.tcl
==================================================================
--- library/package.tcl
+++ library/package.tcl
@@ -407,11 +407,11 @@
 	}
 	append index "\n[eval $cmd]"
     }
 
     set f [open [file join $dir pkgIndex.tcl] w]
-    fconfigure $f -translation lf
+    fconfigure $f -encoding utf-8 -translation lf
     puts $f $index
     close $f
 }
 
 # tclPkgSetup --

Index: library/safe.tcl
==================================================================
--- library/safe.tcl
+++ library/safe.tcl
@@ -935,11 +935,11 @@
 	    Log $child "attempt to use the identity encoding"
 	    return -code error "permission denied"
 	}
     } else {
 	set at 0
-	set encoding {}
+	set encoding utf-8
     }
     if {$argc != 1} {
 	set msg "wrong # args: should be \"source ?-encoding E? fileName\""
 	Log $child "$msg ($args)"
 	return -code error $msg
@@ -978,14 +978,11 @@
     # doesn't leak so much. [Bug 2913625]
     set old [::interp eval $child {info script}]
     set replacementMsg "script error"
     set code [catch {
 	set f [open $realfile]
-	fconfigure $f -eofchar \032
-	if {$encoding ne ""} {
-	    fconfigure $f -encoding $encoding
-	}
+	fconfigure $f -encoding $encoding -eofchar \032
 	set contents [read $f]
 	close $f
 	::interp eval $child [list info script $file]
     } msg opt]
     if {$code == 0} {

Index: library/tm.tcl
==================================================================
--- library/tm.tcl
+++ library/tm.tcl
@@ -265,11 +265,11 @@
 		    #
 		    # Right now LOCATE's implementation assumes that the path
 		    # of the package file is the last element in the list.
 
 		    package ifneeded $pkgname $pkgversion \
-			"[::list package provide $pkgname $pkgversion];[::list source -encoding utf-8 $file]"
+			"[::list package provide $pkgname $pkgversion];[::list source $file]"
 
 		    # We abort in this unknown handler only if we got a
 		    # satisfying candidate for the requested package.
 		    # Otherwise we still have to fallback to the regular
 		    # package search to complete the processing.

Index: tests/source.test
==================================================================
--- tests/source.test
+++ tests/source.test
@@ -112,11 +112,11 @@
     set out [open $sourcefile w]
     fconfigure $out -encoding utf-8
     puts $out "\ufeffset y new-y"
     close $out
     set y old-y
-    source -encoding utf-8 $sourcefile
+    source $sourcefile
     return $y
 } -cleanup {
     removeFile $sourcefile
 } -result {new-y}
 
@@ -224,11 +224,11 @@
     fconfigure $f -encoding utf-8
     puts $f "set symbol(square-root) \u221A; set x correct"
     close $f
 } -body {
     set x unset
-    source -encoding utf-8 $sourcefile
+    source $sourcefile
     set x
 } -cleanup {
     removeFile source.file
 } -result correct
 test source-7.2 {source -encoding test} -setup {
@@ -267,11 +267,11 @@
     set f [open $sourcefile w]
     fconfigure $f -encoding utf-8
     puts $f "proc \u20ac {} {return foo}"
     close $f
 } -body {
-    source -encoding utf-8 $sourcefile
+    source $sourcefile
     \u20ac
 } -cleanup {
     removeFile source.file
     rename \u20ac {}
 } -result foo

Index: unix/README
==================================================================
--- unix/README
+++ unix/README
@@ -89,11 +89,11 @@
 	--enable-dtrace		Enable tcl DTrace provider (if DTrace is
 				available on the platform), c.f. tclDTrace.d
 				for descriptions of the probes made available,
 				see http://wiki.tcl.tk/DTrace for more details
 	--with-encoding=ENCODING Specifies the encoding for compile-time
-				configuration values. Defaults to iso8859-1,
+				configuration values. Defaults to utf-8,
 				which is also sufficient for ASCII.
 	--with-tzdata=FLAG	Specifies whether to install timezone data. By
 				default, the configure script tries to detect
 				whether a usable timezone database is present
 				on the system already.

Index: unix/configure
==================================================================
--- unix/configure
+++ unix/configure
@@ -1428,11 +1428,11 @@
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
   --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
   --with-encoding         encoding for configuration values (default:
-                          iso8859-1)
+                          utf-8)
   --with-system-libtommath
                           use external libtommath (default: true if available,
                           false otherwise)
   --with-tzdata           install timezone data (default: autodetect)
 
@@ -3980,11 +3980,11 @@
 #define TCL_CFGVAL_ENCODING "${with_tcencoding}"
 _ACEOF
 
     else
 
-$as_echo "#define TCL_CFGVAL_ENCODING \"iso8859-1\"" >>confdefs.h
+$as_echo "#define TCL_CFGVAL_ENCODING \"utf-8\"" >>confdefs.h
 
     fi
 
 
 #--------------------------------------------------------------------
@@ -9736,13 +9736,10 @@
 
     fi
 
 $as_echo "#define USE_VFORK 1" >>confdefs.h
 
-
-$as_echo "#define TCL_DEFAULT_ENCODING \"utf-8\"" >>confdefs.h
-
 
 $as_echo "#define TCL_LOAD_FROM_MEMORY 1" >>confdefs.h
 
 
 $as_echo "#define TCL_WIDE_CLICKS 1" >>confdefs.h

Index: unix/configure.ac
==================================================================
--- unix/configure.ac
+++ unix/configure.ac
@@ -604,12 +604,10 @@
     if test $tcl_corefoundation = yes; then
 	AC_CHECK_HEADERS(libkern/OSAtomic.h)
 	AC_CHECK_FUNCS(OSSpinLockLock)
     fi
     AC_DEFINE(USE_VFORK, 1, [Should we use vfork() instead of fork()?])
-    AC_DEFINE(TCL_DEFAULT_ENCODING, "utf-8",
-	[Are we to override what our default encoding is?])
     AC_DEFINE(TCL_LOAD_FROM_MEMORY, 1,
 	[Can this platform load code from memory?])
     AC_DEFINE(TCL_WIDE_CLICKS, 1,
 	[Does this platform have wide high-resolution clicks?])
     AC_CHECK_HEADERS(AvailabilityMacros.h)

Index: unix/tcl.m4
==================================================================
--- unix/tcl.m4
+++ unix/tcl.m4
@@ -2443,18 +2443,18 @@
 #--------------------------------------------------------------------
 
 AC_DEFUN([SC_TCL_CFG_ENCODING], [
     AC_ARG_WITH(encoding,
 	AC_HELP_STRING([--with-encoding],
-	    [encoding for configuration values (default: iso8859-1)]),
+	    [encoding for configuration values (default: utf-8)]),
 	with_tcencoding=${withval})
 
     if test x"${with_tcencoding}" != x ; then
 	AC_DEFINE_UNQUOTED(TCL_CFGVAL_ENCODING,"${with_tcencoding}",
 	    [What encoding should be used for embedded configuration info?])
     else
-	AC_DEFINE(TCL_CFGVAL_ENCODING,"iso8859-1",
+	AC_DEFINE(TCL_CFGVAL_ENCODING,"utf-8",
 	    [What encoding should be used for embedded configuration info?])
     fi
 ])
 
 #--------------------------------------------------------------------

Index: unix/tclConfig.h.in
==================================================================
--- unix/tclConfig.h.in
+++ unix/tclConfig.h.in
@@ -413,13 +413,10 @@
 #undef TCL_COMPILE_DEBUG
 
 /* Are bytecode statistics enabled? */
 #undef TCL_COMPILE_STATS
 
-/* Are we to override what our default encoding is? */
-#undef TCL_DEFAULT_ENCODING
-
 /* Is Tcl built as a framework? */
 #undef TCL_FRAMEWORK
 
 /* Can this platform load code from memory? */
 #undef TCL_LOAD_FROM_MEMORY

Index: unix/tclUnixInit.c
==================================================================
--- unix/tclUnixInit.c
+++ unix/tclUnixInit.c
@@ -90,11 +90,11 @@
  * on the platform. However, there is always a final fallback, and this value
  * is it. Make sure it is a real Tcl encoding.
  */
 
 #ifndef TCL_DEFAULT_ENCODING
-#define TCL_DEFAULT_ENCODING "iso8859-1"
+#define TCL_DEFAULT_ENCODING "utf-8"
 #endif
 
 /*
  * Default directory in which to look for Tcl library scripts. The symbol is
  * defined by Makefile.

Index: win/configure
==================================================================
--- win/configure
+++ win/configure
@@ -3745,12 +3745,11 @@
 	cat >>confdefs.h <<_ACEOF
 #define TCL_CFGVAL_ENCODING "${with_tcencoding}"
 _ACEOF
 
     else
-	# Default encoding on windows is not "iso8859-1"
-	$as_echo "#define TCL_CFGVAL_ENCODING \"cp1252\"" >>confdefs.h
+	$as_echo "#define TCL_CFGVAL_ENCODING \"utf-8\"" >>confdefs.h
 
     fi
 
 
 #--------------------------------------------------------------------

Index: win/tcl.m4
==================================================================
--- win/tcl.m4
+++ win/tcl.m4
@@ -1083,12 +1083,11 @@
     AC_ARG_WITH(encoding, [  --with-encoding         encoding for configuration values], with_tcencoding=${withval})
 
     if test x"${with_tcencoding}" != x ; then
 	AC_DEFINE_UNQUOTED(TCL_CFGVAL_ENCODING,"${with_tcencoding}")
     else
-	# Default encoding on windows is not "iso8859-1"
-	AC_DEFINE(TCL_CFGVAL_ENCODING,"cp1252")
+	AC_DEFINE(TCL_CFGVAL_ENCODING,"utf-8")
     fi
 ])
 
 #--------------------------------------------------------------------
 # SC_EMBED_MANIFEST