diff -r 31daac3a85ea -r 4bd480886813 src/Pure/System/build.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/System/build.scala	Tue Jul 17 15:56:19 2012 +0200
@@ -0,0 +1,60 @@
+/*  Title:      Pure/System/build.scala
+    Author:     Makarius
+
+Build and manage Isabelle sessions.
+*/
+
+package isabelle
+
+
+object Build
+{
+  /* command line entry point */
+
+  private object Bool
+  {
+    def unapply(s: String): Option[Boolean] =
+      s match {
+        case "true" => Some(true)
+        case "false" => Some(false)
+        case _ => None
+      }
+  }
+
+  def main(args: Array[String])
+  {
+    def bad_args()
+    {
+      java.lang.System.err.println("Bad arguments: " + args.toString)
+      sys.exit(2)
+    }
+
+    args.toList match {
+      case Bool(all_sessions) :: Bool(build_images) :: Bool(list_only) :: rest =>
+        rest.indexWhere(_ == "\n") match {
+          case -1 => bad_args()
+          case i =>
+            val (options, rest1) = rest.splitAt(i)
+            val sessions = rest1.tail
+            val rc = build(all_sessions, build_images, list_only, options, sessions)
+            sys.exit(rc)
+        }
+      case _ => bad_args()
+    }
+  }
+
+
+  /* build */
+
+  def build(all_sessions: Boolean, build_images: Boolean, list_only: Boolean,
+    options: List[String], sessions: List[String]): Int =
+  {
+    val rc = 1
+
+    println("options = " + options.toString)
+    println("sessions = " + sessions.toString)
+
+    rc
+  }
+}
+