Module Lwt_mutex

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 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))

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

type t

Type of Lwt mutexes

valcreate : ``unit-> t

create () creates a new mutex, which is initially unlocked

vallock :t ->``unitLwt.t

lock mutex lockcs the mutex, that is:

if the mutex is unlocked, then it is marked as locked and lock returns immediately
if it is locked, then lock waits for all threads waiting on the mutex to terminate, then it resumes when the last one unlocks the mutex

Note: threads are woken up in the same order they try to lock the mutex

valunlock :t -> unit

unlock mutex unlock the mutex if no threads is waiting on it. Otherwise it will eventually removes the first one and resumes it.

valis_locked :t -> bool

locked mutex returns whether mutex is currently locked

valis_empty :t -> bool

is_empty mutex returns true if they are no thread waiting on the mutex, and false otherwise

valwith_lock :t ->``(``unit-> 'a Lwt.t)`` -> 'a Lwt.t

with_lock lock f is used to lock a mutex within a block scope. The function f () is called with the mutex locked, and its result is returned from the call to with_lock. If an exception is raised from f, the mutex is also unlocked before the scope of with_lock is exited.

Module Lwt_mutex

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