diff --git a/lib/info.c b/lib/info.c
index bde958453d..7fbb47c8e1 100644
--- a/lib/info.c
+++ b/lib/info.c
@@ -1251,11 +1251,7 @@ ktxPrintKTX2InfoJSONForNamedFile(const char* const filename, ktx_uint32_t base_i
 {
     FILE* file = NULL;
 
-#ifdef _WIN32
-    fopen_s(&file, filename, "rb");
-#else
-    file = fopen(filename, "rb");
-#endif
+    file = ktxFOpenUTF8(filename, "rb");
 
     if (!file)
         return KTX_FILE_OPEN_FAILED;
diff --git a/lib/ktxint.h b/lib/ktxint.h
index 7656aa9e48..a5c156578e 100644
--- a/lib/ktxint.h
+++ b/lib/ktxint.h
@@ -293,6 +293,52 @@ KTX_error_code ktxUncompressZLIBInt(unsigned char* pDest,
 
 KTX_error_code printKTX2Info2(ktxStream* src, KTX_header2* header);
 
+/*
+ * fopen a file identified by a UTF-8 path.
+ */
+#if defined(_WIN32)
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
+#include <assert.h>
+#include <windows.h>
+#include <shellapi.h>
+#include <stdlib.h>
+
+// For Windows, we convert the UTF-8 path and mode to UTF-16 path and use _wfopen
+// which correctly handles unicode characters.
+static inline FILE* ktxFOpenUTF8(char const* path, char const* mode) {
+    int wpLen = MultiByteToWideChar(CP_UTF8, 0, path, -1, NULL, 0);
+    int wmLen = MultiByteToWideChar(CP_UTF8, 0, mode, -1, NULL, 0);
+    FILE* fp = NULL;
+    if (wpLen > 0 && wmLen > 0)
+    {
+        wchar_t* wpath = (wchar_t*)malloc(wpLen * sizeof(wchar_t));
+        wchar_t* wmode = (wchar_t*)malloc(wmLen * sizeof(wchar_t));
+        MultiByteToWideChar(CP_UTF8, 0, path, -1, wpath, wpLen);
+        MultiByteToWideChar(CP_UTF8, 0, mode, -1, wmode, wmLen);
+        // Returned errmo_t value is also set in the global errno.
+        // Apps use that for error detail as libktx only returns
+        // KTX_FILE_OPEN_FAILED.
+        (void)_wfopen_s(&fp, wpath, wmode);
+        free(wpath);
+        free(wmode);
+        return fp;
+    } else {
+        assert(KTX_FALSE && "ktxFOpenUTF8 called with zero length path or mode.");
+        return NULL;
+    }
+}
+#else
+// For other platforms there is no need for any conversion, they support UTF-8 natively
+static inline FILE* ktxFOpenUTF8(char const* path, char const* mode) {
+    return fopen(path, mode);
+}
+#endif
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/texture.c b/lib/texture.c
index a4b046543f..76821e195b 100644
--- a/lib/texture.c
+++ b/lib/texture.c
@@ -408,7 +408,7 @@ ktxTexture_CreateFromNamedFile(const char* const filename,
     if (filename == NULL || newTex == NULL)
         return KTX_INVALID_VALUE;
 
-    file = fopen(filename, "rb");
+    file = ktxFOpenUTF8(filename, "rb");
     if (!file)
        return KTX_FILE_OPEN_FAILED;
 
diff --git a/lib/texture1.c b/lib/texture1.c
index 23a6b7d9c5..1591f3b6dc 100644
--- a/lib/texture1.c
+++ b/lib/texture1.c
@@ -458,6 +458,9 @@ ktxTexture1_constructFromStdioStream(ktxTexture1* This, FILE* stdioStream,
  * @memberof ktxTexture1 @private
  * @brief Construct a ktxTexture1 from a named KTX file.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * See ktxTextureInt_constructFromStream for details.
  *
  * @param[in] This pointer to a ktxTextureInt-sized block of memory to
@@ -484,7 +487,7 @@ ktxTexture1_constructFromNamedFile(ktxTexture1* This,
     if (This == NULL || filename == NULL)
         return KTX_INVALID_VALUE;
 
-    file = fopen(filename, "rb");
+    file = ktxFOpenUTF8(filename, "rb");
     if (!file)
        return KTX_FILE_OPEN_FAILED;
 
@@ -681,6 +684,9 @@ ktxTexture1_CreateFromStdioStream(FILE* stdioStream,
  * The address of a newly created texture reflecting the contents of the
  * file is written to the location pointed at by @p newTex.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * The create flag KTX_TEXTURE_CREATE_LOAD_IMAGE_DATA_BIT should not be set,
  * if the ktxTexture1 is ultimately to be uploaded to OpenGL or Vulkan. This
  * will minimize memory usage by allowing, for example, loading the images
diff --git a/lib/texture2.c b/lib/texture2.c
index 436f9bcf39..173e5026d9 100644
--- a/lib/texture2.c
+++ b/lib/texture2.c
@@ -1101,6 +1101,9 @@ ktxTexture2_constructFromStdioStream(ktxTexture2* This, FILE* stdioStream,
  * @~English
  * @brief Construct a ktxTexture from a named KTX file.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * See ktxTextureInt_constructFromStream for details.
  *
  * @param[in] This pointer to a ktxTextureInt-sized block of memory to
@@ -1127,7 +1130,7 @@ ktxTexture2_constructFromNamedFile(ktxTexture2* This,
     if (This == NULL || filename == NULL)
         return KTX_INVALID_VALUE;
 
-    file = fopen(filename, "rb");
+    file = ktxFOpenUTF8(filename, "rb");
     if (!file)
        return KTX_FILE_OPEN_FAILED;
 
@@ -1378,6 +1381,9 @@ ktxTexture2_CreateFromStdioStream(FILE* stdioStream,
  * The address of a newly created ktxTexture2 reflecting the contents of the
  * file is written to the location pointed at by @p newTex.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * The create flag KTX_TEXTURE_CREATE_LOAD_IMAGE_DATA_BIT should not be set,
  * if the ktxTexture is ultimately to be uploaded to OpenGL or Vulkan. This
  * will minimize memory usage by allowing, for example, loading the images
diff --git a/lib/writer1.c b/lib/writer1.c
index 7408917705..b9c8dd9e09 100644
--- a/lib/writer1.c
+++ b/lib/writer1.c
@@ -397,6 +397,9 @@ ktxTexture1_WriteToStdioStream(ktxTexture1* This, FILE* dstsstr)
  * @~English
  * @brief Write a ktxTexture object to a named file in KTX format.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * @param[in] This      pointer to the target ktxTexture object.
  * @param[in] dstname   destination file name.
  *
@@ -422,7 +425,7 @@ ktxTexture1_WriteToNamedFile(ktxTexture1* This, const char* const dstname)
     if (!This)
         return KTX_INVALID_VALUE;
 
-    dst = fopen(dstname, "wb");
+    dst = ktxFOpenUTF8(dstname, "wb");
     if (dst) {
         result = ktxTexture1_WriteToStdioStream(This, dst);
         fclose(dst);
@@ -842,6 +845,9 @@ ktxTexture1_WriteKTX2ToStdioStream(ktxTexture1* This, FILE* dstsstr)
  * @~English
  * @brief Write a ktxTexture object to a named file in KTX2 format.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * Callers are strongly urged to include a KTXwriter item in the texture's metadata.
  * It can be added by code, similar to the following, prior to calling this
  * function.
@@ -878,7 +884,7 @@ ktxTexture1_WriteKTX2ToNamedFile(ktxTexture1* This, const char* const dstname)
     if (!This)
         return KTX_INVALID_VALUE;
 
-    dst = fopen(dstname, "wb");
+    dst = ktxFOpenUTF8(dstname, "wb");
     if (dst) {
         result = ktxTexture1_WriteKTX2ToStdioStream(This, dst);
         fclose(dst);
diff --git a/lib/writer2.c b/lib/writer2.c
index 0f26911401..e553e8c613 100644
--- a/lib/writer2.c
+++ b/lib/writer2.c
@@ -632,6 +632,9 @@ ktxTexture2_WriteToStdioStream(ktxTexture2* This, FILE* dstsstr)
  * @~English
  * @brief Write a ktxTexture object to a named file in KTX format.
  *
+ * The file name must be encoded in utf-8. On Windows convert unicode names
+ * to utf-8 with @c WideCharToMultiByte(CP_UTF8, ...) before calling.
+ *
  * Callers are strongly urged to include a KTXwriter item in the texture's metadata.
  * It can be added by code, similar to the following, prior to calling this
  * function.
@@ -668,7 +671,7 @@ ktxTexture2_WriteToNamedFile(ktxTexture2* This, const char* const dstname)
     if (!This)
         return KTX_INVALID_VALUE;
 
-    dst = fopen(dstname, "wb");
+    dst = ktxFOpenUTF8(dstname, "wb");
     if (dst) {
         result = ktxTexture2_WriteToStdioStream(This, dst);
         fclose(dst);
diff --git a/utils/argparser.cpp b/utils/argparser.cpp
index f5dbc164e6..48620971f7 100644
--- a/utils/argparser.cpp
+++ b/utils/argparser.cpp
@@ -23,29 +23,31 @@
 #include <assert.h>
 #include "argparser.h"
 
+using namespace std;
+
 /*
  * Construct from a string of arguments.
  */
-argvector::argvector(const _tstring& sArgs)
+argvector::argvector(const string& sArgs)
 {
-    const _tstring sep(_T(" \t\n\r\v\f"));
+    const string sep(" \t\n\r\v\f");
     size_t pos;
 
     pos = sArgs.find_first_not_of(sep);
-    assert(pos != _tstring::npos);
+    assert(pos != string::npos);
 
     do {
         size_t epos = sArgs.find_first_of(sep, pos);
-        size_t len = epos == _tstring::npos ? epos : epos - pos;
+        size_t len = epos == string::npos ? epos : epos - pos;
         push_back(sArgs.substr(pos, len));
         pos = sArgs.find_first_not_of(sep, epos);
-    } while (pos != _tstring::npos);
+    } while (pos != string::npos);
 }
 
 /*
  * Construct from an array of C strings
  */
-argvector::argvector(int argc, const _TCHAR* const* argv)
+argvector::argvector(int argc, const char* const* argv)
 {
     for (int i = 0; i < argc; i++) {
         push_back(argv[i]);
@@ -56,24 +58,24 @@ argvector::argvector(int argc, const _TCHAR* const* argv)
  * Functions the same as getopt_long. See `man 3 getopt_long`.
  */
 int
-argparser::getopt(_tstring* shortopts, const struct option* longopts,
+argparser::getopt(string* shortopts, const struct option* longopts,
                   int* /*longindex*/)
 {
     if (optind == argv.size())
         return -1;
 
-    _tstring arg;
+    string arg;
     arg = argv[optind];
-    if (arg[0] != _T('-') || (arg[0] == _T('-') && arg.size() == 1))
+    if (arg[0] != '-' || (arg[0] == '-' && arg.size() == 1))
         return -1;
     optind++;
 
     int retval = '?';
-    if (arg.compare(0, 2, _T("--")) == 0) {
+    if (arg.compare(0, 2, "--") == 0) {
         if (arg.size() == 2) return -1; // " -- " separates options and files
         const struct option* opt = longopts;
         while (opt->name != nullptr) {
-            if (arg.compare(2, _tstring::npos, opt->name) == 0) {
+            if (arg.compare(2, string::npos, opt->name) == 0) {
                 retval = opt->val;
                 if (opt->has_arg != option::no_argument) {
                     if (optind >= argv.size() || (optarg = argv[optind++])[0] == '-') {
@@ -91,9 +93,9 @@ argparser::getopt(_tstring* shortopts, const struct option* longopts,
             }
             opt++;
         }
-    } else if (shortopts != nullptr && arg.compare(0, 1, _T("-")) == 0) {
+    } else if (shortopts != nullptr && arg.compare(0, 1, "-") == 0) {
         size_t pos = shortopts->find(arg.substr(1, 1));
-        if (pos != _tstring::npos) {
+        if (pos != string::npos) {
             retval = (*shortopts)[pos];
             if (pos < shortopts->length()
                 && ((*shortopts)[++pos] == ':' || (*shortopts)[pos] == ';')) {
@@ -118,7 +120,7 @@ std::istream& operator >> (std::istream& stream, const skip& x)
     stream >> std::noskipws;
 
     char c;
-    const _TCHAR* text = x.text;
+    const char* text = x.text;
     while (stream && *text++)
         stream >> c;
 
diff --git a/utils/argparser.h b/utils/argparser.h
index 14dfa9cec2..d977bc3936 100644
--- a/utils/argparser.h
+++ b/utils/argparser.h
@@ -13,26 +13,12 @@
 #include <sstream>
 #include <string>
 #include <vector>
-#if defined(_WIN32)
-  #include <tchar.h>
-#elif !defined(_TCHAR)
-  #define _TCHAR char
-  #define _T(x) x
-#endif
-#if !defined(_tstring)
-  #if defined(_UNICODE)
-    #define _tstring std::wstring
-  #else
-    #define _tstring std::string
-  #endif
-#endif
 
-
-class argvector : public std::vector<_tstring> {
+class argvector : public std::vector<std::string> {
   public:
     argvector() { };
-    argvector(const _tstring& argstring);
-    argvector(int argc, const _TCHAR* const* argv);
+    argvector(const std::string& argstring);
+    argvector(int argc, const char* const* argv);
 };
 
 class argparser {
@@ -46,17 +32,17 @@ class argparser {
         option(const char* name, has_arg_t has_arg, int* flag, int val) : name(name), has_arg(has_arg), flag(flag), val(val) {}
     };
 
-    _tstring optarg;
+    std::string optarg;
     unsigned int optind;
     argvector argv;
 
     argparser(argvector& argv, unsigned int startindex = 0)
         : optind(startindex), argv(argv) { }
 
-    argparser(int argc, const _TCHAR* const* argv1)
+    argparser(int argc, const char* const* argv1)
         : optind(1), argv(argc, argv1)  { }
 
-    int getopt(_tstring* shortopts, const struct option* longopts,
+    int getopt(std::string* shortopts, const struct option* longopts,
                int* longindex = nullptr);
 };
 
@@ -66,8 +52,8 @@ class argparser {
 // does not check whether the skipped characters are the same as it
 struct skip
 {
-    const _TCHAR* text;
-    skip(const _TCHAR* text) : text(text) {}
+    const char* text;
+    skip(const char* text) : text(text) {}
 };
 
 std::istream& operator >> (std::istream& stream, const skip& x);
diff --git a/utils/ktxapp.h b/utils/ktxapp.h
index d069e12d6a..09c9f45678 100644
--- a/utils/ktxapp.h
+++ b/utils/ktxapp.h
@@ -22,6 +22,7 @@
 #include <ktx.h>
 
 #include "argparser.h"
+#include "platform_utils.h"
 
 #define QUOTE(x) #x
 #define STR(x) QUOTE(x)
@@ -90,7 +91,7 @@ struct clamped
 
 class ktxApp {
   public:
-    virtual int main(int argc, _TCHAR* argv[]) = 0;
+    virtual int main(int argc, char* argv[]) = 0;
     virtual void usage() {
         cerr <<
             "  -h, --help    Print this usage message and exit.\n"
@@ -100,11 +101,12 @@ class ktxApp {
 #endif
             ;
     };
+    string& getName() { return name;  }
 
   protected:
     struct commandOptions {
-        std::vector<_tstring> infiles;
-        _tstring outfile;
+        std::vector<string> infiles;
+        string outfile;
         int test;
         int warn;
         int launchDebugger;
@@ -168,16 +170,16 @@ class ktxApp {
      * @return A stdio FILE* for the created file. If the file already exists
      *         returns nullptr and sets errno to EEXIST.
      */
-    static FILE* fopen_write_if_not_exists(const _tstring& path) {
-        FILE* file = ::_tfopen(path.c_str(), "wxb");
+    static FILE* fopen_write_if_not_exists(const string& path) {
+        FILE* file = ::fopenUTF8(path, "wxb");
         if (!file && errno == EINVAL) {
-            file = ::_tfopen(path.c_str(), "r");
+            file = ::fopenUTF8(path, "r");
             if (file) {
                 fclose(file);
                 file = nullptr;
                 errno = EEXIST;
             } else {
-                file = ::_tfopen(path.c_str(), "wb");
+                file = ::fopenUTF8(path, "wb");
             }
         }
         return file;
@@ -198,7 +200,7 @@ class ktxApp {
 
     enum StdinUse { eDisallowStdin, eAllowStdin };
     enum OutfilePos { eNone, eFirst, eLast };
-    void processCommandLine(int argc, _TCHAR* argv[],
+    void processCommandLine(int argc, char* argv[],
                             StdinUse stdinStat = eAllowStdin,
                             OutfilePos outfilePos = eNone)
     {
@@ -207,14 +209,14 @@ class ktxApp {
 
         name = argv[0];
         // For consistent Id, only use the stem of name;
-        slash = name.find_last_of(_T('\\'));
-        if (slash == _tstring::npos)
-            slash = name.find_last_of(_T('/'));
-        if (slash != _tstring::npos)
+        slash = name.find_last_of('\\');
+        if (slash == string::npos)
+            slash = name.find_last_of('/');
+        if (slash != string::npos)
             name.erase(0, slash+1);  // Remove directory name.
-        dot = name.find_last_of(_T('.'));
-            if (dot != _tstring::npos)
-                name.erase(dot, _tstring::npos); // Remove extension.
+        dot = name.find_last_of('.');
+            if (dot != string::npos)
+                name.erase(dot, string::npos); // Remove extension.
 
         argparser parser(argc, argv);
         processOptions(parser);
@@ -225,9 +227,9 @@ class ktxApp {
                 options.outfile = parser.argv[i++];
             uint32_t infileCount = outfilePos == eLast ? argc - 1 : argc;
             for (; i < infileCount; i++) {
-                if (parser.argv[i][0] == _T('@')) {
+                if (parser.argv[i][0] == '@') {
                     if (!loadFileList(parser.argv[i],
-                                      parser.argv[i][1] == _T('@'),
+                                      parser.argv[i][1] == '@',
                                       options.infiles)) {
                         exit(1);
                     }
@@ -236,9 +238,9 @@ class ktxApp {
                 }
             }
             if (options.infiles.size() > 1) {
-                std::vector<_tstring>::const_iterator it;
+                std::vector<string>::const_iterator it;
                 for (it = options.infiles.begin(); it < options.infiles.end(); it++) {
-                    if (it->compare(_T("-")) == 0) {
+                    if (it->compare("-") == 0) {
                         error("cannot use stdin as one among many inputs.");
                         usage();
                         exit(1);
@@ -251,7 +253,7 @@ class ktxApp {
 
         if (options.infiles.size() == 0) {
             if (stdinStat == eAllowStdin) {
-                options.infiles.push_back(_T("-")); // Use stdin as 0 files.
+                options.infiles.push_back("-"); // Use stdin as 0 files.
             } else {
                 error("need some input files.");
                 usage();
@@ -263,26 +265,21 @@ class ktxApp {
         }
     }
 
-    bool loadFileList(const _tstring &f, bool relativize,
-                      vector<_tstring>& filenames)
+    bool loadFileList(const string &f, bool relativize,
+                      vector<string>& filenames)
     {
-        _tstring listName(f);
+        string listName(f);
         listName.erase(0, relativize ? 2 : 1);
 
         FILE *lf = nullptr;
-#if defined(_WIN32)
-        _tfopen_s(&lf, listName.c_str(), "r");
-#else
-        lf = _tfopen(listName.c_str(), "r");
-#endif
-
+        lf = fopenUTF8(listName, "r");
         if (!lf) {
             error("failed opening filename list: \"%s\": %s\n",
                   listName.c_str(), strerror(errno));
             return false;
         }
 
-        _tstring dirname;
+        string dirname;
 
         if (relativize) {
             size_t dirnameEnd = listName.find_last_of('/');
@@ -311,7 +308,7 @@ class ktxApp {
 
             string readFilename(p);
             while (readFilename.size()) {
-                if (readFilename[0] == _T(' '))
+                if (readFilename[0] == ' ')
                   readFilename.erase(0, 1);
                 else
                   break;
@@ -319,7 +316,7 @@ class ktxApp {
 
             while (readFilename.size()) {
                 const char c = readFilename.back();
-                if ((c == _T(' ')) || (c == _T('\n')) || (c == _T('\r')))
+                if ((c == ' ') || (c == '\n') || (c == '\r'))
                   readFilename.erase(readFilename.size() - 1, 1);
                 else
                   break;
@@ -422,9 +419,9 @@ class ktxApp {
     }
 #endif
 
-    _tstring        name;
-    _tstring&       version;
-    _tstring&       defaultVersion;
+    string        name;
+    string&       version;
+    string&       defaultVersion;
 
     commandOptions& options;
 
@@ -447,7 +444,29 @@ class ktxApp {
         { nullptr, argparser::option::no_argument, nullptr, 0 }
     };
 
-    _tstring short_opts = _T("hv");
+    string short_opts = "hv";
 };
 
+extern ktxApp& theApp;
+
+/** @internal
+ * @~English
+ * @brief Common main for all derived classes.
+ * 
+ * Handles rewriting of argv to UTF-8 on Windows.
+ * Each app needs to initialize @c theApp to
+ * point to an instance of itself.
+ */
+int main(int argc, char* argv[])
+{
+    InitUTF8CLI(argc, argv);
+#if 0
+    if (!SetConsoleOutputCP(CP_UTF8)) {
+        cerr << theApp.getName() << "warning: failed to set UTF-8 code page for console output."
+             << endl;
+    }
+#endif
+    return theApp.main(argc, argv);
+}
+
 
diff --git a/utils/platform_utils.h b/utils/platform_utils.h
index 7152af674d..5f3efb7927 100644
--- a/utils/platform_utils.h
+++ b/utils/platform_utils.h
@@ -9,8 +9,6 @@
 #include <iostream>
 #include <memory>
 #include <vector>
-#include <fmt/ostream.h>
-#include <fmt/printf.h>
 
 #if defined(_WIN32)
 #ifndef WIN32_LEAN_AND_MEAN
@@ -43,15 +41,15 @@ inline std::string DecodeUTF8Path(std::string path) {
 }
 #endif
 
-inline void InitUTF8CLI(int& argc, _TCHAR* argv[]) {
-#if defined(_WIN32) && !defined(_UNICODE)
+inline void InitUTF8CLI(int& argc, char* argv[]) {
+#if defined(_WIN32)
     // Windows does not support UTF-8 argv so we have to manually acquire it
-    static std::vector<std::unique_ptr<_TCHAR[]>> utf8Argv(argc);
+    static std::vector<std::unique_ptr<char[]>> utf8Argv(argc);
     LPWSTR commandLine = GetCommandLineW();
     LPWSTR* wideArgv = CommandLineToArgvW(commandLine, &argc);
     for (int i = 0; i < argc; ++i) {
         int byteSize = WideCharToMultiByte(CP_UTF8, 0, wideArgv[i], -1, nullptr, 0, nullptr, nullptr);
-        utf8Argv[i] = std::make_unique<_TCHAR[]>(byteSize);
+        utf8Argv[i] = std::make_unique<char[]>(byteSize);
         WideCharToMultiByte(CP_UTF8, 0, wideArgv[i], -1, utf8Argv[i].get(), byteSize, nullptr, nullptr);
         argv[i] = utf8Argv[i].get();
     }
@@ -61,3 +59,22 @@ inline void InitUTF8CLI(int& argc, _TCHAR* argv[]) {
     (void)argv;
 #endif
 }
+
+inline FILE* fopenUTF8(const std::string& path, const std::string& mode) {
+#if defined(_WIN32)
+    FILE* fp;
+    // Returned errmo_t value is also set in the global errno.
+    (void)_wfopen_s(&fp, DecodeUTF8Path(path).c_str(), DecodeUTF8Path(mode).c_str());
+    return fp;
+#else
+    return fopen(path.c_str(), mode.c_str());
+#endif
+}
+
+inline int unlinkUTF8(const std::string& path) {
+#if defined(_WIN32)
+    return _wunlink(DecodeUTF8Path(path).c_str());
+#else
+    return unlink(path.c_str());
+#endif
+}
diff --git a/utils/scapp.h b/utils/scapp.h
index ea2bb757bf..24ca263790 100644
--- a/utils/scapp.h
+++ b/utils/scapp.h
@@ -558,7 +558,7 @@ class scApp : public ktxApp {
     }
 
     int encode(ktxTexture2* texture, const string& swizzle,
-               const _tstring& filename);
+               const string& filename);
 
     void usage()
     {
@@ -1075,7 +1075,7 @@ scApp::processOption(argparser& parser, int opt)
  */
 int
 scApp::encode(ktxTexture2* texture, const string& swizzle,
-              const _tstring& filename)
+              const string& filename)
 {
     ktx_error_code_e result;
 
diff --git a/utils/stdafx.h b/utils/stdafx.h
index 7513ba4949..e6a68716a1 100644
--- a/utils/stdafx.h
+++ b/utils/stdafx.h
@@ -15,47 +15,14 @@
 #include <stdio.h>
 #ifdef _WIN32
   #include <io.h>
-  #include <tchar.h>
   #if _MSC_VER < 1900
     #define snprintf _snprintf
   #endif
 #else
   #include <unistd.h>
-
   #define _setmode(x, y) 0
-  #define _tmain main
-  #define _tcsncmp strncmp
-  #define _tcscmp strcmp
-  #define _tgetenv getenv
-  #define _tcscpy strcpy
-  #define _tcsncpy strncpy
-  #define _tcsnpcpy strnpcpy
-  #define _stscanf sscanf
-  #define _tcslen strlen
-  #define _tcscat strcat
-  #define _tcsrchr strrchr
-  #define _tcschr strchr
-  #define _tfopen fopen
-  #define _trename rename
-  #define _tunlink unlink
-  #if !defined(_TCHAR)
-    #define _TCHAR char
-    #define _T(x) x
-  #endif
-#endif
-#if !defined(_tstring)
-  #if defined(_UNICODE)
-    #define _tstring std::wstring
-  #else
-    #define _tstring std::string
-  #endif
 #endif
+
 #include <fcntl.h>
 #include <errno.h>
 #include <string.h>
-
-#if defined(_UNICODE)
-    #define _tstring std::wstring
-#else
-    #define _tstring std::string
-#endif