src/Pure/System/cygwin_init.scala

 */
 
 package isabelle
 
 
-import java.lang.System
 import java.io.{File => JFile, BufferedReader, InputStreamReader}
 import java.nio.file.{Paths, Files}
 import java.awt.{GraphicsEnvironment, Point, Font}
 import javax.swing.ImageIcon
 

 import scala.swing.event.ButtonClicked
 
 
 object Cygwin_Init
 {
-  /* command-line entry point */
+  /* main GUI entry point */
 
-  def main(args: Array[String]) =
-  {
-    GUI.init_laf()
-    try {
-      require(Platform.is_windows)
-
-      val isabelle_home = System.getProperty("isabelle.home")
-      if (isabelle_home == null || isabelle_home == "")
-        error("Unknown Isabelle home directory")
-      if (!(new JFile(isabelle_home)).isDirectory)
-        error("Bad Isabelle home directory: " + quote(isabelle_home))
-
-      Swing_Thread.later { main_frame(isabelle_home) }
-    }
-    catch {
-      case exn: Throwable =>
-        GUI.error_dialog(null, "Isabelle init failure", GUI.scrollable_text(Exn.message(exn)))
-        sys.exit(2)
-    }
-  }
-
-
-  /* main window */
-
-  private def main_frame(isabelle_home: String) = new MainFrame
+  def main_frame(isabelle_home: String, start: => Unit) = new MainFrame
   {
     title = "Isabelle system initialization"
     iconImage = new ImageIcon(isabelle_home + "\\lib\\logo\\isabelle.gif").getImage
 
     val layout_panel = new BorderPanel

 
 
     /* exit button */
 
     var _return_code: Option[Int] = None
-    def maybe_exit(): Unit = _return_code.foreach(sys.exit(_))
+    def maybe_exit()
+    {
+      _return_code match {
+        case None =>
+        case Some(0) => start
+        case Some(rc) => sys.exit(rc)
+      }
+    }
 
     def return_code(rc: Int): Unit =
       Swing_Thread.later {
         _return_code = Some(rc)
         button.peer.getRootPane.setDefaultButton(button.peer)

     location = new Point(point.x - size.width / 2, point.y - size.height / 2)
     visible = true
 
     default_thread_pool.submit(() =>
       try {
-        init(isabelle_home, echo)
+        init_filesystem(isabelle_home, echo)
         return_code(0)
       }
       catch {
         case exn: Throwable =>
           text_area.append("Error:\n" + Exn.message(exn) + "\n")

   }
 
 
   /* init Cygwin file-system */
 
-  private def init(isabelle_home: String, echo: String => Unit)
+  private def init_filesystem(isabelle_home: String, echo: String => Unit)
   {
-    val cygwin_root = isabelle_home + "\\contrib\\cygwin"
-
-    if (!(new JFile(cygwin_root)).isDirectory)
-      error("Bad Isabelle Cygwin directory: " + quote(cygwin_root))
-
     def execute(args: String*): Int =
     {
       val cwd = new JFile(isabelle_home)
       val env = Map("CYGWIN" -> "nodosfilewarning")
       val proc = Isabelle_System.raw_execute(cwd, env, true, args: _*)

     echo("Initializing Cygwin:")
 
     echo("symlinks ...")
     val symlinks =
     {
-      val path = (new JFile(cygwin_root, "isabelle\\symlinks")).toPath
+      val path = (new JFile("contrib\\cygwin\\isabelle\\symlinks")).toPath
       Files.readAllLines(path, UTF8.charset).toArray.toList.asInstanceOf[List[String]]
     }
     @tailrec def recover_symlinks(list: List[String]): Unit =
     {
       list match {

       }
     }
     recover_symlinks(symlinks)
 
     echo("rebaseall ...")
-    execute(cygwin_root + "\\bin\\dash.exe", "/isabelle/rebaseall")
+    execute("contrib\\cygwin\\bin\\dash.exe", "/isabelle/rebaseall")
 
     echo("postinstall ...")
-    execute(cygwin_root + "\\bin\\bash.exe", "/isabelle/postinstall")
+    execute("contrib\\cygwin\\bin\\bash.exe", "/isabelle/postinstall")
 
     echo("init ...")
-    System.setProperty("cygwin.root", cygwin_root)
     Isabelle_System.init()
     echo("OK")
   }
 }