What a Windows editor saves, and a standard user's Windows install (from dev 9d6f66456a3d)

- CRLF line endings are read as newlines on every system (the reader used
  to delete the pair, collapsing a Notepad++ file into one line on Linux
  and macOS); a leading UTF-8 byte-order mark is ignored; a UTF-16 or
  Windows-1252 source is refused with the encoding, the place and the
  remedy named. .gitattributes pins LF in every clone.
- Windows source install: the repository path must hold no space (GNU
  Make), accented letters are fine (every linker input is relative now);
  python.org's Python is selected ahead of an MSYS2 one that poppler pulls
  in; TeX Live goes to its Windows default C:\texlive\2026.
- The Python binding needs an ASCII installation path on Windows, and its
  suite says so there.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

.gitattributes

@@ -0,0 +1,9 @@
+# Every text file is LF in the working tree on every system, whatever
+# core.autocrlf says: .kt, .k and the shell suites must be LF (2026-09-26).
+* text=auto eol=lf
+# Shipped verbatim, as the foundries wrote them (CRLF): never normalized.
+fnt/**/*.txt -text
+sks/document/fonts/**/*.txt -text
+# Not shipped; kept byte-stable.
+dbg/** -text
+sks.alpha/** -text

README.md

@@ -53,7 +53,7 @@ are regenerated on each release — patches cannot be merged directly.
 Report problems (or send patches) to the author; accepted changes are
 applied to the development tree and appear in a following snapshot.
 
-This snapshot was assembled from development commit `d5f9c20b94b3`.
+This snapshot was assembled from development commit `9d6f66456a3d`.
 
 ## License
 

doc/edit/notepadpp/README.md

@@ -26,6 +26,9 @@ current file, and this package uses exactly those two things.
   version qualifies).
 - For the Run commands: `python` on the `Path`, which the Klammertext
   installation already needs.
+- Files saved as UTF-8 (Notepad++'s default for new files; **Encoding ￫
+  Convert to UTF-8** for an older one). Line endings do not matter, and
+  a file in another encoding is refused by `ktext` with the remedy named.
 
 ## Install the highlighting
 

doc/install/windows_source_install.md

@@ -97,11 +97,17 @@ git clone https://git.andykopra.com/ack/klammertext.git
 cd klammertext
 ```
 
-Git for Windows must not translate line endings: Klammertext's `.kt`
+The repository's path must contain no space: GNU Make cannot build under
-files, `.k` files and shell scripts are LF files. The clone above respects
+one. If your user name has a space in it (`C:\Users\Anna Maria`), clone
-that as long as `core.autocrlf` is not `true`; check with `git config
+somewhere else, for example into `C:\klammertext`, and write that path
---get core.autocrlf` and, if it prints `true`, set it to `false` and clone
+wherever `C:\Users\<you>\klammertext` appears below. Accented letters in
-again.
+the path are fine for the commands; only the Python binding (`kpy\`) needs
+a path of plain ASCII letters.
+
+Klammertext's `.kt` files, `.k` files and shell scripts are LF files, and
+the repository says so itself (`.gitattributes`), so the clone is correct
+whatever your Git's `core.autocrlf` setting. A `.kt` you write with
+Windows line endings is fine too: ktext reads them as newlines.
 
 
 ## Environment variables
@@ -110,14 +116,14 @@ Klammertext's runtime environment is one self-configuring file, the same
 one Linux and macOS use. Source it from the UCRT64 shell's profile:
 
 ```bash
-echo 'source /c/Users/<you>/klammertext/env/runtime.env' >> ~/.bashrc
+echo 'source "/c/Users/<you>/klammertext/env/runtime.env"' >> ~/.bashrc
 source ~/.bashrc
 ```
 
 On Windows it sets `KLAMMERTEXT_HOME` and `TMPDIR` in the form Windows
 programs understand (`C:/Users/<you>/klammertext`), adds `bin/` to `PATH`,
-finds a TeX Live installed under `C:\Users\<you>\external\texlive\<year>`
+finds a TeX Live installed under `C:\texlive\<year>` (see below), and
-(see below), and sets `PYTHON=python`. Nothing is edited by hand.
+sets `PYTHON=python`. Nothing is edited by hand.
 
 
 ## Build
@@ -171,26 +177,28 @@ ktext hello.kt -t html          # writes hello\index.html
 ## TeX Live (for PDF output)
 
 The Standard Klammer Set renders PDF with **XeLaTeX**. Install TeX Live's
-`scheme-small` plus the packages the SKS needs into
+`scheme-small` plus the packages the SKS needs into `C:\texlive\2026`,
-`C:\Users\<you>\external\texlive\2026`, where `runtime.env` finds it. This
+TeX Live's own default location on Windows, where `runtime.env` finds it.
-is a download of about 600 MB and takes twenty to thirty minutes.
+(It also looks under `C:\Users\<you>\external\texlive\<year>`, the place
+the Linux and macOS pages use, but TeX Live does not work under a path
+with a space or an accented letter, and a user name may have either.)
+This is a download of about 600 MB and takes twenty to thirty minutes.
 
 1. Download `install-tl.zip` from a CTAN mirror, for example
    `https://ctan.math.illinois.edu/systems/texlive/tlnet/install-tl.zip`,
    and unzip it. It unpacks into a folder named `install-tl-<date>`.
 
-2. In that folder, create a file `texlive.profile` with this content,
+2. In that folder, create a file `texlive.profile` with this content:
-   replacing `<you>` with your Windows user name:
 
    ```
    selected_scheme scheme-small
-   TEXDIR C:/Users/<you>/external/texlive/2026
+   TEXDIR C:/texlive/2026
-   TEXMFLOCAL C:/Users/<you>/external/texlive/2026/texmf-local
+   TEXMFLOCAL C:/texlive/2026/texmf-local
-   TEXMFSYSCONFIG C:/Users/<you>/external/texlive/2026/texmf-config
+   TEXMFSYSCONFIG C:/texlive/2026/texmf-config
-   TEXMFSYSVAR C:/Users/<you>/external/texlive/2026/texmf-var
+   TEXMFSYSVAR C:/texlive/2026/texmf-var
-   TEXMFHOME C:/Users/<you>/texmf
+   TEXMFHOME C:/texlive/2026/texmf-home
-   TEXMFVAR C:/Users/<you>/.texlive2026/texmf-var
+   TEXMFVAR C:/texlive/2026/texmf-uvar
-   TEXMFCONFIG C:/Users/<you>/.texlive2026/texmf-config
+   TEXMFCONFIG C:/texlive/2026/texmf-uconfig
    tlpdbopt_install_docfiles 0
    tlpdbopt_install_srcfiles 0
    tlpdbopt_autobackup 0
@@ -214,7 +222,7 @@ is a download of about 600 MB and takes twenty to thirty minutes.
    installs on Linux and macOS — and rebuild the formats:
 
    ```powershell
-   $tl = "$env:USERPROFILE\external\texlive\2026\bin\windows"
+   $tl = "C:\texlive\2026\bin\windows"
    $env:Path = "$tl;$env:Path"
    & "$tl\tlmgr.bat" option repository https://ctan.math.illinois.edu/systems/texlive/tlnet
    & "$tl\tlmgr.bat" install adjustbox collectbox collection-fontsrecommended enumitem fontaxes footmisc inconsolata layouts mdframed multirow needspace opensans pict2e textpos titlesec upquote zref
@@ -244,7 +252,7 @@ from PowerShell):
 ```powershell
 [Environment]::SetEnvironmentVariable("KLAMMERTEXT_HOME", "C:\Users\<you>\klammertext", "User")
 $p = [Environment]::GetEnvironmentVariable("Path", "User")
-[Environment]::SetEnvironmentVariable("Path", "$p;C:\Users\<you>\klammertext\bin;C:\Users\<you>\external\texlive\2026\bin\windows", "User")
+[Environment]::SetEnvironmentVariable("Path", "$p;C:\Users\<you>\klammertext\bin;C:\texlive\2026\bin\windows", "User")
 ```
 
 (Not `setx Path "$env:Path;…"`: `$env:Path` is the machine and user
@@ -374,8 +382,15 @@ incomplete or `KLAMMERTEXT_HOME` points elsewhere.
 **"The 'xelatex' command required to make PDF files is not installed".**
 TeX Live's `bin\windows` directory is not on the `Path` of the shell you
 are using. In the UCRT64 shell `runtime.env` adds it when the tree is under
-`C:\Users\<you>\external\texlive\<year>`; in PowerShell add it as shown
+`C:\texlive\<year>` or `C:\Users\<you>\external\texlive\<year>`; in
-above.
+PowerShell add it as shown above.
+
+**`make` stops at once with `"python" is C:/msys64/ucrt64/python, not
+python.org's interpreter`.** MSYS2's own Python was installed as a
+dependency (poppler brings it), and in the UCRT64 shell it precedes
+python.org's on the `Path`. `runtime.env` puts python.org's first: source
+it (a new UCRT64 shell does, once the line is in `~/.bashrc`) and run
+`make` again.
 
 **`git` or `python` are "command not found" in the UCRT64 shell.**
 `MSYS2_PATH_TYPE` is not set to `inherit`, or the shell was opened before

env/makefile.env

@@ -34,6 +34,19 @@ endif
 ifneq (,$(filter MINGW% MSYS%,$(UNAME_S)))
 PYTHON        := python
 PYTHON_PREFIX := $(shell cygpath -m "$$($(PYTHON) -c 'import sys; print(sys.base_prefix)')")
+# The interpreter "python" resolves to must be python.org's, which has an
+# import library under libs/.  MSYS2's own python (installed as a dependency
+# of poppler, through glib2) sits in /ucrt64/bin ahead of it and has none:
+# a build against it compiles nothing (no Include/Python.h) or embeds an
+# interpreter without the user's pip packages.  env/runtime.env puts
+# python.org's directory first; refuse rather than build the wrong thing.
+# (Asked of the interpreter, not $(wildcard): the prefix "C:/Program Files"
+# has a space, on which wildcard splits.)
+ifeq (,$(NOPYTHON))
+ifneq (yes,$(shell $(PYTHON) -c 'import os, sys; print("yes" if os.path.isdir(os.path.join(sys.base_prefix, "libs")) else "no")'))
+$(error "python" is $(PYTHON_PREFIX)/python, not python.org's interpreter (no libs/ there); source env/runtime.env, which puts python.org's Python first on PATH)
+endif
+endif
 PYTHON_INC    := -I"$(PYTHON_PREFIX)/Include"
 PYTHON_LIB    := -L"$(PYTHON_PREFIX)/libs" -l$(shell $(PYTHON) -c 'import sys; print("python%d%d" % sys.version_info[:2])')
 else

env/runtime.env

@@ -31,6 +31,21 @@ case "$_kt_uname" in
         export KLAMMERTEXT_HOME="$(cygpath -m "$KLAMMERTEXT_HOME")"
         export TMPDIR="$(cygpath -m "${TMPDIR:-/tmp}")"
         export PYTHON="${PYTHON:-python}"     # python.org installs no python3
+        # "python" must be python.org's interpreter: the build embeds it and
+        # pip installs OpenImageIO into it.  But the UCRT64 shell puts
+        # /ucrt64/bin first on PATH, and an MSYS2 package installed as a
+        # dependency (poppler -> glib2 -> python) puts ITS python there, which
+        # then shadows python.org's for make, the suites and the tooling.
+        # python.org's launcher knows only python.org installs: put the
+        # directory of the interpreter it selects first.  (Its output ends
+        # in CR LF, hence the tr.)
+        if command -v py >/dev/null 2>&1; then
+            _kt_py="$(py -3 -c 'import sys; print(sys.executable)' 2>/dev/null | tr -d '\r')"
+            if [ -n "$_kt_py" ]; then
+                export PATH="$(dirname "$(cygpath -u "$_kt_py")"):$PATH"
+            fi
+            unset _kt_py
+        fi
         ;;
 esac
 
@@ -50,13 +65,19 @@ fi
 # just returns nothing. The -path pattern keeps the 4-digit-year restriction.
 # Windows: a user installs under the Windows home, %USERPROFILE%\external
 # (MSYS2's $HOME is C:\msys64\home\<user>, which no Windows guide would name).
-_kt_tlroot="$HOME/external/texlive"
+# Windows also: TeX Live's own default, C:\texlive\<year> -- the place for a
-case "$_kt_uname" in MINGW*|MSYS*) _kt_tlroot="$(cygpath -u "$USERPROFILE")/external/texlive";; esac
+# user whose profile path holds a space or an accented letter, which TeX
-_kt_tl="$(find "$_kt_tlroot" -maxdepth 3 -type d \
+# Live's installer and kpathsea do not take (2026-09-26).  The newest YEAR
-             -path "*/[0-9][0-9][0-9][0-9]/bin/$_kt_arch" 2>/dev/null \
+# wins across both roots (the year is the sort key, not the path).
-         | sort -V | tail -1)"
+_kt_tlroot="$HOME/external/texlive"; _kt_tlroot2=""
+case "$_kt_uname" in MINGW*|MSYS*) _kt_tlroot="$(cygpath -u "$USERPROFILE")/external/texlive"; _kt_tlroot2="/c/texlive";; esac
+_kt_tl="$( { find "$_kt_tlroot" -maxdepth 3 -type d \
+                -path "*/[0-9][0-9][0-9][0-9]/bin/$_kt_arch" 2>/dev/null
+             [ -n "$_kt_tlroot2" ] && find "$_kt_tlroot2" -maxdepth 3 -type d \
+                -path "*/[0-9][0-9][0-9][0-9]/bin/$_kt_arch" 2>/dev/null; } \
+         | awk -F/ '{ print $(NF-2) " " $0 }' | sort -V | tail -1 | cut -d' ' -f2-)"
 [ -n "$_kt_tl" ] && export KLAMMERTEXT_TEXLIVE_BIN="$_kt_tl"
-unset _kt_tl _kt_arch _kt_tlroot
+unset _kt_tl _kt_arch _kt_tlroot _kt_tlroot2
 
 # --- PATH (TeX Live appended only if one was found) ---------------------------
 export PATH="$_kt_home_posix/bin:$_kt_home_posix/tst${KLAMMERTEXT_TEXLIVE_BIN:+:$KLAMMERTEXT_TEXLIVE_BIN}:$PATH"

kpy/Makefile

@@ -18,7 +18,9 @@ K := $(KLAMMERTEXT_HOME)
 
 include $(K)/env/makefile.env
 
-LIBDIR := $(K)/lib
+# Relative, never $(K)/...: the mingw linker cannot open a path holding a
+# non-ASCII letter (C:/Übungen/...), while the compiler can (2026-09-26).
+LIBDIR := ../lib
 LIBRARY := $(LIBDIR)/$(KLAMMERTEXT_LIBFILE)
 
 EXT_SUFFIX := $(shell $(PYTHON) -c 'import sysconfig; print(sysconfig.get_config_var("EXT_SUFFIX"))')

mac/file.cpp

@@ -325,7 +325,20 @@ std::string string_from_file(const std::string& pathname, bool strip_surrounding
                 } else {
                 result = buffer.str();
 
-                result = string_replace(result, "\r\n", ""); // Urgh.
+                // A leading UTF-8 byte-order mark is not text: Windows tools
+                // (PowerShell's Set-Content, Notepad's "UTF-8 with BOM") put
+                // one at the start of a file, and without this a .kt beginning
+                // "@document" was reported as "Word not parsed" at 1:1, the
+                // offending word invisible (decided 2026-09-26).
+                if (result.compare(0, 3, "\xEF\xBB\xBF") == 0)
+                    result.erase(0, 3);
+
+                // Windows line endings become newlines. (This line DELETED the
+                // pair until 2026-09-26, so on Linux and macOS a file written by
+                // Notepad++ or a DOS-mode Emacs collapsed into one line and its
+                // spans no longer matched; on Windows the C runtime's text mode
+                // had already translated the pair, which hid the bug there.)
+                result = string_replace(result, "\r\n", "\n");
 
 
                 if (std::regex_match(pathname, klammertext_filename_re)) {
@@ -575,6 +588,67 @@ void write_to_cache(const std::string& cache_dir, const std::string& basename, c
     string_to_file(output_filename, text);
 }
 
+// The offset of the first byte that is not part of well-formed UTF-8, or
+// npos.  Overlong forms, surrogates and code points above 10FFFF are rejected
+// like a decoder would (RFC 3629, table 3-7 of the Unicode standard).
+static std::size_t first_invalid_utf8(const std::string& s)
+{
+    const auto n = s.size();
+    for (std::size_t i = 0; i < n;) {
+        const unsigned char b = static_cast<unsigned char>(s[i]);
+        std::size_t len; unsigned char lo = 0x80, hi = 0xBF;
+        if (b < 0x80) { i += 1; continue; }
+        else if (b >= 0xC2 && b <= 0xDF) len = 2;
+        else if (b == 0xE0) { len = 3; lo = 0xA0; }
+        else if (b >= 0xE1 && b <= 0xEC) len = 3;
+        else if (b == 0xED) { len = 3; hi = 0x9F; }
+        else if (b >= 0xEE && b <= 0xEF) len = 3;
+        else if (b == 0xF0) { len = 4; lo = 0x90; }
+        else if (b >= 0xF1 && b <= 0xF3) len = 4;
+        else if (b == 0xF4) { len = 4; hi = 0x8F; }
+        else return i;
+        if (i + len > n) return i;
+        for (std::size_t k = 1; k < len; ++k) {
+            const unsigned char c = static_cast<unsigned char>(s[i + k]);
+            const unsigned char l = (k == 1) ? lo : 0x80, h = (k == 1) ? hi : 0xBF;
+            if (c < l || c > h) return i;
+        }
+        i += len;
+    }
+    return std::string::npos;
+}
+
+std::string klammertext_from_file(const std::string& pathname)
+{
+    std::string text = string_from_file(pathname);
+    // A UTF-16 file (Notepad++ offers "UCS-2 LE BOM") begins with FF FE or
+    // FE FF; read as bytes it is NUL-interleaved and every word is "not
+    // parsed".  Name the encoding and the remedy instead.
+    if (text.size() >= 2 && ((static_cast<unsigned char>(text[0]) == 0xFF && static_cast<unsigned char>(text[1]) == 0xFE)
+                          || (static_cast<unsigned char>(text[0]) == 0xFE && static_cast<unsigned char>(text[1]) == 0xFF))) {
+        throw File_error("File \"" + pathname + "\" is UTF-16 (it begins with a byte-order mark), and Klammertext reads UTF-8. "
+                         "Save it as UTF-8 in your editor (Notepad++: Encoding, Convert to UTF-8) and run the command again.",
+                         Locator(fs::path(pathname), 1, 0));   // the Locator's character counts from 0
+    }
+    // A file saved as ANSI (Windows-1252, the default of some editors) is
+    // not UTF-8 from its first accented letter on; the bytes otherwise
+    // reach the embedded Python and fail there with a message about
+    // something else entirely.
+    if (const std::size_t bad = first_invalid_utf8(text); bad != std::string::npos) {
+        int line = 1, chr = 1;
+        for (std::size_t i = 0; i < bad; ++i) {
+            if (text[i] == '\n') { ++line; chr = 1; }
+            else if ((static_cast<unsigned char>(text[i]) & 0xC0) != 0x80) ++chr;   // count characters, not bytes
+        }
+        char hex[8]; std::snprintf(hex, sizeof hex, "%02X", static_cast<unsigned char>(text[bad]));
+        throw File_error("File \"" + pathname + "\" is not UTF-8 at line " + std::to_string(line) + ", character "
+                         + std::to_string(chr) + " (byte " + hex + "), and Klammertext reads UTF-8. "
+                         "Save it as UTF-8 in your editor (Notepad++: Encoding, Convert to UTF-8) and run the command again.",
+                         Locator(fs::path(pathname), line, chr - 1));
+    }
+    return text;
+}
+
 std::string read_from_cache(const std::string& cache_dir, const std::string& basename)
 {
     std::string input_filename = cache_dir + "/" + basename;

mac/file.h

@@ -70,6 +70,12 @@ std::vector<std::string> group_filename_tokens(
 std::vector<std::string> resolve_filename_list(
     const std::string& text, const std::string& base_dir="");
 std::string string_from_file(const std::string& pathname, bool strip_surrounding_whitespace=false);
+// A Klammertext source (a .kt, a .k, a @read file): string_from_file() plus
+// the check that it IS text Klammertext can read -- a File_error names the
+// first byte that is not UTF-8 (line and character), or a UTF-16 file by its
+// byte-order mark, with what to do in an editor.  string_from_file() itself
+// stays permissive: it also reads XeTeX logs and a shell command's stderr.
+std::string klammertext_from_file(const std::string& pathname);
 void string_to_file(const std::string& pathname, std::string contents);
 std::vector<std::string> get_files_in_directory(const std::string& dir);
 std::string find_file(const std::string& basename, std::vector<std::string> search_path,

mac/klammerset_registry.cpp

@@ -221,7 +221,7 @@ static std::string klammerset_description(const fs::path& declaration)
 {
     std::string text {};
     try {
-        text = string_from_file(declaration.string());
+        text = klammertext_from_file(declaration.string());
     } catch (...) {
         return "";
     }

mac/machine.cpp

@@ -491,7 +491,7 @@ void Machine::read(const fs::path& pathname)
     // :cpp libraries live next to the file that uses them).
     m_state.add_search_dir(fs::absolute(pathname).parent_path().string());
     m_state.open_frame("Machine state: " + pathname.string());
-    input(string_from_file(pathname.string()), pathname.generic_string());
+    input(klammertext_from_file(pathname.string()), pathname.generic_string());
     m_sources.push_back(pathname);
 }
 
@@ -552,7 +552,7 @@ void Machine::expand_read_katoms(
 
                 input_filename = fs::canonical(input_filename);
                 m_state.add_search_dir(input_filename.parent_path().string());
-                std::string text = trim_right(string_from_file(input_filename.string()));
+                std::string text = trim_right(klammertext_from_file(input_filename.string()));
                 katom_list ks = katomize_lines(line_split(text), input_filename.generic_string());
                 // ks = 
                 process_katoms(
@@ -684,7 +684,7 @@ void Machine::load_klammerset_files(const Klammerset& klammerset, katom_iter ins
         pathname = fs::canonical(pathname);
         loaded_files.push_back(pathname.generic_string());
         m_state.add_search_dir(pathname.parent_path().string());
-        std::string text = trim_right(string_from_file(pathname.string()));
+        std::string text = trim_right(klammertext_from_file(pathname.string()));
         katom_list ks = katomize_lines(line_split(text), pathname.generic_string());
         process_katoms(ks, pathname.generic_string());
         loaded.insert(loaded.end(), ks.begin(), ks.end());

ref/Makefile

@@ -19,7 +19,9 @@ include $(K)/env/makefile.env
 # CPPFLAGS already carries -I$(KLAMMERTEXT_HOME)/mac, which is every header
 # reflect.cpp includes (machine, character, error, show).  No local -I.
 
-LIBDIR := $(K)/lib
+# Relative, never $(K)/...: the mingw linker cannot open a path holding a
+# non-ASCII letter (C:/Übungen/...), while the compiler can (2026-09-26).
+LIBDIR := ../lib
 LIBRARY := $(LIBDIR)/$(KLAMMERTEXT_LIBFILE)
 REFLECT := reflect$(DSO)
 

sks/document/Makefile

@@ -11,7 +11,9 @@ include $(K)/env/makefile.env
 LOCAL_CPPFLAGS := -I$(KM) -I$(KS)/kutil -I$(KS)/target
 
 # Shared library location
-LIBDIR := $(K)/lib
+# Relative, never $(K)/...: the mingw linker cannot open a path holding a
+# non-ASCII letter (C:/Übungen/...), while the compiler can (2026-09-26).
+LIBDIR := ../../lib
 LIBRARY := $(LIBDIR)/$(KLAMMERTEXT_LIBFILE)
 
 # The product: document.so, on Windows document.dll (makefile.env's DSO)
@@ -25,8 +27,8 @@ LOCAL_OBJECTS := document_class.o document_html.o document_latex.o heading.o ref
 LOCAL_DEPFILES := document_class.d document_html.d document_latex.d heading.d reference.d document.d
 
 # External object files from sks/ (mac/*.o now in the shared library)
-SKS_OBJECTS := $(KS)/kutil/kutil.o $(KS)/kutil/klammer_base.o \
+SKS_OBJECTS := ../kutil/kutil.o ../kutil/klammer_base.o \
-               $(KS)/target/html_util.o $(KS)/target/latex_util.o
+               ../target/html_util.o ../target/latex_util.o
 
 ALL_OBJECTS := $(LOCAL_OBJECTS) $(SKS_OBJECTS)
 

tst/filename_test.sh

@@ -36,6 +36,10 @@ mkdir "$DIR/my dir"
 printf 'ALPHA\n' > "$DIR/my file.kt"
 printf 'BETA\n'  > "$DIR/b.kt"
 printf 'GAMMA\n' > "$DIR/my dir/c.kt"
+printf '\357\273\277DELTA\n' > "$DIR/bom.kt"     # a UTF-8 byte-order mark, then the text
+printf 'EPSILON\r\nZETA\r\n' > "$DIR/crlf.kt"      # Windows line endings
+printf '\377\376h\000i\000\n\000' > "$DIR/utf16.kt"    # UTF-16LE with its byte-order mark
+printf 'ETA\nTHETA M\374ller\n' > "$DIR/cp1252.kt"   # Windows-1252: an umlaut that is not UTF-8
 cd "$DIR" || exit 1
 
 # check TEST_NAME EXPECTED_STDOUT EXPECTED_STDERR_SUBSTRING KTEXT_ARGS...
@@ -151,6 +155,37 @@ check_error "8. unrescuable name is reported as written" \
       "no such.kt" \
       "no such.kt" -d --klammersets none
 
+# A leading UTF-8 byte-order mark is ignored (2026-09-26): Windows tools write
+# one, and it was reported as "Word not parsed" at 1:1 with an invisible word.
+check "9. a leading UTF-8 BOM in the input file is ignored" \
+      "DELTA" "" \
+      bom.kt -d --klammersets none
+
+check "10. a leading UTF-8 BOM in a @read file is ignored" \
+      "DELTA" "" \
+      -s '@read bom.kt @' -d --klammersets none
+
+# Windows line endings are newlines (2026-09-26): the reader DELETED the pair,
+# so on Linux and macOS a CRLF file collapsed into one line.
+check "11. CRLF line endings are read as newlines" \
+      $'EPSILON\nZETA' "" \
+      crlf.kt -d --klammersets none
+
+# What a Windows editor can also save (2026-09-26): a UTF-16 file and an
+# ANSI (Windows-1252) file are named as such, with the remedy, instead of
+# "Word not parsed" or a failure inside the embedded Python.
+check_error "12. a UTF-16 file is named as such" \
+      "UTF-16" \
+      utf16.kt -d --klammersets none
+
+check_error "13. a Windows-1252 file is located at its first non-UTF-8 byte" \
+      "line 2, character 8" \
+      cp1252.kt -d --klammersets none
+
+check_error "14. ... through @read as well" \
+      "not UTF-8" \
+      -s '@read cp1252.kt @' -d --klammersets none
+
 echo
 echo "======================="
 echo "Results: ${green}$PASS passed${reset}, ${red}$FAIL failed${reset}"

tst/kpy_test.sh

@@ -49,6 +49,19 @@ trap 'rm -rf "$OUTF" "$ERRF" "$WORK"' EXIT
 if command -v cygpath >/dev/null 2>&1; then sep=';'; else sep=':'; fi
 export PYTHONPATH="$K/kpy${PYTHONPATH:+$sep$PYTHONPATH}"
 
+# On Windows the binding cannot load under a KLAMMERTEXT_HOME that holds a
+# non-ASCII character: inside python.exe, a process without Klammertext's
+# UTF-8 manifest, the narrow getenv() is the ANSI code page, and the engine
+# takes every path as UTF-8.  A documented limitation, not a defect to fix
+# (TODO 70 (f), Andy 2026-09-26): the binding needs an ASCII installation
+# path there.  Say so and skip, rather than fail every case with a decode
+# error that names no cause.
+if command -v cygpath >/dev/null 2>&1 && LC_ALL=C grep -q '[^ -~]' <<<"$K"; then
+    echo "SKIP kpy_test: KLAMMERTEXT_HOME ($K) holds a non-ASCII character, and the Python binding needs an ASCII installation path on Windows (TODO 70 (f))"
+    echo "Passed: 0, Failed: 0"
+    exit 0
+fi
+
 # A DEBUG=1 build instruments the module with AddressSanitizer, and an
 # instrumented extension imported into an uninstrumented python needs the
 # ASan runtime loaded FIRST -- the import otherwise fails with "ASan runtime