(*  Title:      Pure/ML-Systems/ml_system.ML

    Author:     Makarius

ML system and platform operations.

*)

signature ML_SYSTEM =

sig

  val name: string

  val is_polyml: bool

  val is_smlnj: bool

  val platform: string

  val platform_is_cygwin: bool

  val share_common_data: unit -> unit

  val save_state: string -> unit

end;

structure ML_System: ML_SYSTEM =

struct

val SOME name = OS.Process.getEnv "ML_SYSTEM";

val is_polyml = String.isPrefix "polyml" name;

val is_smlnj = String.isPrefix "smlnj" name;

val SOME platform = OS.Process.getEnv "ML_PLATFORM";

val platform_is_cygwin = String.isSuffix "cygwin" platform;

fun share_common_data () = ();

fun save_state _ = raise Fail "Cannot save state -- undefined operation";

end;