Module Lwt_timeout

Instructions: Use this module in your project

In the IDE (CLion, Visual Studio Code, Xcode, etc.) you use for your DkSDK project:

Add the following to your project's dependencies/CMakeLists.txt:

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DkSDKProject_DeclareAvailable(lwt
    CONSTRAINT "= 5.6.1"
    FINDLIBS lwt lwt.unix)
DkSDKProject_MakeAvailable(lwt)

Add the Findlib::lwt library to any desired targets in src/*/CMakeLists.txt:

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target_link_libraries(YourPackage_YourLibraryName
     # ... existing libraries, if any ...
     Findlib::lwt)

Click your IDE's Build button

Not using DkSDK?

FIRST, do one or all of the following:

Run:
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```
opam install lwt.5.6.1
```

Edit your dune-project and add:

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(package
  (name YourExistingPackage)
  (depends
  ; ... existing dependenices ...
  (lwt (>= 5.6.1))))

Then run:

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dune build *.opam # if this fails, run: dune build

Edit your <package>.opam file and add:

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depends: [
  # ... existing dependencies ...
  "lwt" {>= "5.6.1"}
]

Then run:

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opam install . --deps-only

FINALLY, add the lwt.unix library to any desired (library)and/or (executable) targets in your **/dune files:

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(library
  (name YourLibrary)
  ; ... existing library options ...
  (libraries
    ; ... existing libraries ...
    lwt.unix))

(executable
  (name YourExecutable)
  ; ... existing executable options ...
  (libraries
    ; ... existing libraries ...
    lwt.unix))

type t

valcreate : ``int->``(``unit->unit)``-> t

Lwt_timeout.create n f creates a new timeout object with duration n seconds. f is the action, a function to be called once the timeout expires. f should not raise exceptions.

The timeout is not started until Lwt_timeout.start is called on it.

valstart :t -> unit

Starts the given timeout.

Starting a timeout that has already been started has the same effect as stopping it, and then restarting it with its original duration. So, suppose you have timeout with a duration of three seconds, which was started two seconds ago. The next call to its action is scheduled for one second in the future. Calling Lwt_timeout.start timeout at this point cancels this upcoming action call, and schedules a call three seconds from now.

valstop :t -> unit

Stops (cancels) the given timeout.

valchange :t ->``int-> unit

Changes the duration of the given timeout.

If the timeout has already been started, it is stopped, and restarted with its new duration. This is similar to how Lwt_timeout.start works on a timeout that has already been started.

valset_exn_handler : ``(``exn->unit)``-> unit

Lwt_timeout.set_exn_handler f sets the handler to be used for exceptions raised by timeout actions. Recall that actions are not allowed to raise exceptions. If they do raise an exception exn despite this, f exn is called.

The default behavior of f exn, set by Lwt_timeout on program startup, is to pass exn to !Lwt.async_exception_hook. The default behavior of that is to terminate the process.

Module Lwt_timeout

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