# Structure Process

Identifier index | Structure index
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    (* OS.Process -- SML Basis Library *)

    type status

    val success   : status
    val failure   : status

    val isSuccess : status -> bool

    val system    : string -> status

    val atExit    : (unit -> unit) -> unit
    val exit      : status -> 'a
    val terminate : status -> 'a
    val sleep     : Time.time -> unit

    val getEnv    : string -> string option

    (*
       Portable functions for manipulating processes.

       [success] is the unique status value that signifies successful
       termination of a process.  Note: MS DOS (sometimes) believes that
       all processes are successful.

       [failure] is a status value that signifies an error during
       execution of a process.  Note that in contrast to the success
       value, there may be several distinct failure values.  Use function
       isSuccess to reliably test for success.

       [isSuccess sv] returns true if the status value sv represents a
       successful execution, false otherwise.  It holds that
       isSuccess success = true and isSuccess failure = false.

       [system cmd] asks the operating system to execute command cmd, and
       returns a status value.

       [atExit act] registers the action act to be executed when the
       current SML program calls Process.exit.  Actions will be executed
       in reverse order of registration.

       [exit i] executes all registered actions, then terminates the SML
       process with completion code i.

       [terminate i] terminates the SML process with completion code i
       (but without executing the registered actions).

       [sleep t] suspends this process for approximately the time
       indicated by t.  The actual time slept depends on the capabilities
       of the underlying system and the system load.  Does not sleep at
       all if t <= Time.zeroTime.

       [getEnv evar] returns SOME s if the environment variable evar is
       defined and is associated with the string s; otherwise NONE.
    *)

Identifier index | Structure index
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Moscow ML 2.10