Class Semaphore

Namespace

Temporalio.Workflows

Assembly

Temporalio.dll

Semaphore is an alternative to Semaphore and SemaphoreSlim built to be deterministic and lightweight. Many of the concepts are similar to SemaphoreSlim.

public class Semaphore

Inheritance

object

Semaphore

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

Semaphore(int)

Initializes a new instance of the Semaphore class.

public Semaphore(int initialCount)

Parameters

initialCount int

The initial number of permits that will be available for requests.

Properties

CurrentCount

Gets the current number of available permits that can be granted concurrently. This is decremented on each successful WaitAsync call and incremented on each Release call.

public int CurrentCount { get; }

Property Value

int

Max

Gets the fixed maximum number of permits that can be granted concurrently. This is always the initialCount value from the constructor.

public int Max { get; init; }

Property Value

int

Methods

Release()

Release a permit for use by another waiter.

public void Release()

Exceptions

InvalidOperationException

Thrown if this release call would extend the CurrentCount beyond Max which means more Release calls were made than successful WaitAsync calls.

WaitAsync(int, CancellationToken?)

Wait for a permit to become available or timeout to be reached. If the task returns true, users must call Release() to properly give the permit back when done.

public Task<bool> WaitAsync(int millisecondsTimeout, CancellationToken? cancellationToken = null)

Parameters

millisecondsTimeout int

Milliseconds until timeout. If this is 0, this is a non-blocking task that will return immediately. If this value is -1 (i.e. Infinite), there is no timeout and the result will always be true on success (at which point you might as well use WaitAsync(CancellationToken?)). Otherwise a timer is started for the timeout and canceled if the wait succeeds.

cancellationToken CancellationToken?

Cancellation token that can interrupt this wait. If unset, this defaults to CancellationToken. Upon cancel, awaiting the resulting task will throw a TaskCanceledException exception.

Returns

Task<bool>

A Task representing the result of the asynchronous operation. The task is true if the wait succeeded and false if it timed out. This task is canceled if the cancellation token is.

WaitAsync(CancellationToken?)

Wait for a permit to become available. If the task succeeds, users must call Release() to properly give the permit back when done.

public Task WaitAsync(CancellationToken? cancellationToken = null)

Parameters

cancellationToken CancellationToken?

Cancellation token that can interrupt this wait. If unset, this defaults to CancellationToken. Upon cancel, awaiting the resulting task will throw a TaskCanceledException exception.

Returns

Task

A Task representing the result of the asynchronous operation. This task is canceled if the cancellation token is.

WaitAsync(TimeSpan, CancellationToken?)

Wait for a permit to become available or timeout to be reached. If the task returns true, users must call Release() to properly give the permit back when done.

public Task<bool> WaitAsync(TimeSpan timeout, CancellationToken? cancellationToken = null)

Parameters

timeout TimeSpan

TimeSpan until timeout. If this is Zero, this is a non-blocking task that will return immediately. If this value is -1ms (i.e. InfiniteTimeSpan), there is no timeout and the result will always be true on success (at which point you might as well use WaitAsync(CancellationToken?)). Otherwise a timer is started for the timeout and canceled if the wait succeeds.

cancellationToken CancellationToken?

Cancellation token that can interrupt this wait. If unset, this defaults to CancellationToken. Upon cancel, awaiting the resulting task will throw a TaskCanceledException exception.

Returns

Task<bool>

A Task representing the result of the asynchronous operation. The task is true if the wait succeeded and false if it timed out. This task is canceled if the cancellation token is.