--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/installer-files/octave-launch.c	Fri Nov 19 06:52:00 2021 -0500
@@ -0,0 +1,300 @@
+/*
+ * Wrapper application to set octave env variables and then run octave
+ * compile with gcc -o octave-launch octave-launch.c -Wl,--subsystem,windows -lshlwapi
+ *
+ * Copyright (C) 2020 John Donoghue <john.donoghue@ieee.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, see <http: *www.gnu.org/licenses/>.
+*/
+
+#include <windows.h>
+#include <shlwapi.h>
+
+static int ParentDir (char *dir)
+{
+  int len = strlen (dir);
+  while (len > 0 && dir[len] != '\\')
+    len --;
+  dir[len] = 0;
+  return len;
+}
+
+char * FilePart (char *dir)
+{
+  int len = strlen (dir);
+  while (len > 0 && dir[len-1] != '\\')
+    len --;
+  return &dir[len];
+}
+
+// Set up environment and launch octave.exe with appropriate
+// arguments.  NOTE: There are corresponding VBS and BAT script
+// versions of this program so any changes here may need to be made in
+// those scripts as well.
+
+int main (int argc, char **argv)
+{
+  PROCESS_INFORMATION pi;
+
+  // FIXME: There are currently have no checks to ensure that the
+  // following fixed-size buffers are sufficiently large.  Maybe it
+  // would be better if we used C++ and std::string objects?  For
+  // buffers that are passed to Windows library functions to hold
+  // output values, is 1024 the correct way to define the size of the
+  // buffer?  Note that the use of sizeof(path)-1 below will fail if
+  // we switch to using
+  //
+  //   char *path = (char *) malloc (...);
+  //
+  // instead of literal character arrays.
+
+  char msyspath[1024];
+  char rootpath[1024];
+  char path[1024];
+  char binpath[1024];
+
+  int gui_arg_found = 0;
+  int no_gui_arg_found = 0;
+  int no_gui_libs = 0;
+  int i;
+
+  /* get path of us which we will assume is the root of the install */
+
+  DWORD nSize = GetModuleFileName (NULL, path, sizeof(path)-1);
+  if (nSize)
+    {
+      while (nSize > 0 && path[nSize] != '\\')
+        nSize --;
+      path[nSize] = '\0';
+    }
+
+  nSize = GetShortPathName (path, rootpath, sizeof(rootpath)-1);
+  if (nSize == 0)
+    StrCpy (rootpath, path);
+
+  SetEnvironmentVariable ("MXE_ROOT", rootpath);
+
+  /* get msys path and set env */
+
+  StrCpy (msyspath, rootpath);
+
+  StrCpy (path, rootpath);
+  StrCat (path, "\\mingw64\\bin\\octave.exe");
+  if (PathFileExists (path))
+    {
+      SetEnvironmentVariable ("MSYSTEM", "MINGW64");
+      StrCat (msyspath, "\\usr");
+      SetEnvironmentVariable ("MSYSPATH", msyspath);
+
+      StrCat (msyspath, "\\bin");
+
+      StrCpy (binpath, rootpath);
+      StrCat (binpath, "\\mingw64\\bin");
+    }
+  else
+    {
+      StrCpy (path, rootpath);
+      StrCat (path, "\\mingw32\\bin\\octave.exe");
+      if (PathFileExists (path))
+        {
+          SetEnvironmentVariable ("MSYSTEM", "MINGW32");
+          StrCat (msyspath, "\\usr");
+          SetEnvironmentVariable ("MSYSPATH", msyspath);
+
+          StrCat (msyspath, "\\bin");
+
+          StrCpy (binpath, rootpath);
+          StrCat (binpath, "\\mingw32\\bin");
+        }
+      else
+        {
+          SetEnvironmentVariable ("MSYSTEM", "MSYS");
+          SetEnvironmentVariable ("MSYSPATH", msyspath);
+
+          StrCat (msyspath, "\\bin");
+
+          StrCpy (binpath, rootpath);
+          StrCat (binpath, "\\bin");
+        }
+    }
+
+  /* binpath is to the octave bin dir so get the parent */
+  StrCpy (path, binpath);
+  ParentDir (path);
+
+ #ifdef SHOW_PATHS
+  MessageBox (NULL, rootpath, "octroot", MB_OK);
+  MessageBox (NULL, path, "octhome", MB_OK);
+  MessageBox (NULL, binpath, "octbin", MB_OK);
+  MessageBox (NULL, msyspath, "msysbin", MB_OK);
+ #endif
+
+  /* qt paths
+   * either %OCT_HOME%\qt5\plugins
+   * or %OCT_HOME\plugins
+   */
+  nSize = strlen (path);
+  StrCat (path, "\\qt5\\plugins");
+  SetEnvironmentVariable ("QT_PLUGIN_PATH", path);
+
+  path[nSize] = '\0';
+
+  /* exe paths */
+  {
+    char pathbuffer[8096];
+    char newpathbuffer[8096];
+
+    nSize = GetEnvironmentVariable ("PATH", pathbuffer, sizeof(pathbuffer)-1);
+    pathbuffer[nSize] = '\0';
+
+    /* set our paths first */
+    StrCpy (newpathbuffer, binpath);
+    StrCat (newpathbuffer, ";");
+    StrCat (newpathbuffer, msyspath);
+    StrCat (newpathbuffer, ";");
+    StrCat (newpathbuffer, pathbuffer);
+
+    SetEnvironmentVariable ("PATH", newpathbuffer);
+  }
+
+  /* other env */
+  SetEnvironmentVariable ("TERM", "cygwin");
+  SetEnvironmentVariable ("GNUTERM", "wxt");
+  SetEnvironmentVariable ("GS", "gs.exe");
+
+  /* home set */
+  nSize = GetEnvironmentVariable ("HOME", path, sizeof(path)-1);
+  if (nSize == 0 || path[0] == 0)
+    {
+      char newhome[1024];
+
+      nSize = GetEnvironmentVariable ("USERPROFILE", path, sizeof(path)-1);
+      if (nSize == 0 || path[0] == 0)
+        {
+          /* build dir from drive and path */
+          char tmpbuff[1024];
+          nSize = GetEnvironmentVariable ("HOMEDRIVE", tmpbuff, sizeof(tmpbuff)-1);
+          if (nSize)
+            StrCpy (path, tmpbuff);
+          else
+            path[0] = '\0';
+
+          nSize = GetEnvironmentVariable ("HOMEPATH", tmpbuff, sizeof(tmpbuff)-1);
+          if (nSize) StrCat (path, tmpbuff);
+        }
+
+      nSize = GetShortPathName (path, newhome, sizeof(newhome)-1);
+
+      if (nSize == 0)
+        {
+          StrCpy (newhome, path);
+        }
+
+      SetEnvironmentVariable ("HOME", newhome);
+    }
+
+  /* check for gui mode */
+  for (i = 1; i < argc; i++)
+    {
+      if (StrCmp (argv[i], "--no-gui-libs") == 0)
+        {
+          if (gui_arg_found)
+            {
+              /* Inconsistent options.  We can't start the GUI without gui libs.
+                 How should we fail?   For now, --no-gui-libs will
+                 override the other options.  */
+            }
+
+          no_gui_libs = 1;
+        }
+      else if (StrCmp (argv[i], "--gui") == 0
+               || StrCmp (argv[i], "--force-gui") == 0)
+        {
+          if (no_gui_libs)
+            {
+              /* Inconsistent options.  We can't start the GUI without gui libs.
+                 How should we fail?   For now, --no-gui-libs will
+                 override the other options.  */
+            }
+
+          gui_arg_found = 1;
+        }
+      else if (StrCmp (argv[i], "--no-gui") == 0)
+        no_gui_arg_found = 1;
+
+      /* NOTE: specifying both --no-gui and --gui is also an
+         inconsistent set of options but we leave it to octave.exe to
+         detect that.  */
+    }
+
+  /* set up process args and start it */
+  {
+    STARTUPINFO si;
+    char argbuffer[4096];
+
+    ZeroMemory (&si, sizeof(si));
+    si.cb = sizeof(si);
+    ZeroMemory (&pi, sizeof(pi));
+
+    StrCpy (path, binpath);
+
+    StrCpy (argbuffer, "octave.exe ");
+    StrCat (path, "\\octave.exe");
+
+    if (! (no_gui_libs || no_gui_arg_found))
+      {
+        /* Unless --no-gui or --no-gui-libs is specified, we will use a GUI window.  */
+        si.dwFlags = STARTF_USESHOWWINDOW;
+
+        /* If none of the options --no-gui, --gui, or --force-gui
+           were specified, then we'll add --gui to start the gui as
+           most Windows users would expect.  */
+
+        if (! gui_arg_found)
+          StrCat (argbuffer, "--gui ");
+      }
+
+    /* quote and append each arg */
+    for (i = 1; i < argc; i++)
+      {
+        StrCat (argbuffer, "\"");
+        StrCat (argbuffer, argv[i]);
+        StrCat (argbuffer, "\" ");
+      }
+
+    /* Start the child process */
+    int status = CreateProcess (path,       // Module name
+                                argbuffer,  // Command line
+                                NULL,       // Process handle not inheritable
+                                NULL,       // Thread handle not inheritable
+                                FALSE,      // Set handle inheritance to FALSE
+                                0,          // No creation flags
+                                NULL,       // Use parent's environment block
+                                NULL,       // Use parent's starting directory
+                                &si,        // Pointer to STARTUPINFO
+                                &pi);       // Pointer to PROCESS_INFORMATION
+
+    if (! status)
+      return 1;
+  }
+
+  /* Wait until child process exits. */
+  WaitForSingleObject (pi.hProcess, INFINITE);
+
+  /* Close process and thread handles */
+  CloseHandle (pi.hProcess);
+  CloseHandle (pi.hThread);
+
+  return 0;
+}