src/Pure/PIDE/prover.scala

 
 General prover operations.
 */
 
 package isabelle
+
+
+import java.io.BufferedReader
 
 
 object Prover
 {
   /* syntax */

   {
     def add_keywords(keywords: Thy_Header.Keywords): Syntax
     def parse_spans(input: CharSequence): List[Command_Span.Span]
     def load_command(name: String): Option[List[String]]
     def load_commands_in(text: String): Boolean
+  }
+
+
+  /* underlying system process */
+
+  trait System_Process
+  {
+    def channel: System_Channel
+    def stdout: BufferedReader
+    def stderr: BufferedReader
+    def terminate: Unit
+    def join: Int
   }
 
 
   /* messages */