src/Pure/Tools/isabelle_process.scala

 
 
   /** main **/
 
   {
+    /* isabelle version */
+
+    {
+      val (msg, rc) = IsabelleSystem.isabelle_tool("version")
+      if (rc != 0) error("Version check failed -- bad Isabelle installation:\n" + msg)
+      put_result(Kind.SYSTEM, null, msg)
+    }
+
 
     /* message fifo */
 
     val message_fifo = IsabelleSystem.mk_fifo()
     def rm_fifo() = IsabelleSystem.rm_fifo(message_fifo)