C# 4 and .NET 4

532 ❘ ChaPTer 20 threAds, tAsks, And synchrOnizAtiOn
}
items[i]++;
Thread.Sleep(50);
}
Console.WriteLine("Writer {0} finished", writer);
}
finally
{
rwl.ExitWriteLock();
}
static void Main()
{
var taskFactory = new TaskFactory(TaskCreationOptions.LongRunning,
TaskContinuationOptions.None);
var tasks = new Task[6];
tasks[0] = taskFactory.StartNew(WriterMethod, 1);
tasks[1] = taskFactory.StartNew(ReaderMethod, 1);
tasks[2] = taskFactory.StartNew(ReaderMethod, 2);
tasks[3] = taskFactory.StartNew(WriterMethod, 2);
tasks[4] = taskFactory.StartNew(ReaderMethod, 3);
tasks[5] = taskFactory.StartNew(ReaderMethod, 4);
}
}
}
for (int i = 0; i < 6; i++)
{
tasks[i].Wait();
}
code snippet ReaderWriterSample/Program.cs
With a run of the application here, the first writer gets the lock first. The second writer and all readers need
to wait. Next, the readers can work concurrently, while the second writer still waits for the resource.
Writer 1 acquired the lock
Writer 2 waiting for the write lock
current reader count: 0
Writer 2 waiting for the write lock
current reader count: 0
Writer 2 waiting for the write lock
current reader count: 0
Writer 2 waiting for the write lock
current reader count: 0
Writer 1 finished
reader 4, loop: 0, item: 1
reader 1, loop: 0, item: 1
Writer 2 waiting for the write lock
current reader count: 4
reader 2, loop: 0, item: 1
reader 3, loop: 0, item: 1
reader 4, loop: 1, item: 2
reader 1, loop: 1, item: 2
reader 3, loop: 1, item: 2
reader 2, loop: 1, item: 2
Writer 2 waiting for the write lock
current reader count: 4
reader 4, loop: 2, item: 3
reader 1, loop: 2, item: 3
reader 2, loop: 2, item: 3
reader 3, loop: 2, item: 3
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