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Hello.

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Welcome back.

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So in this lesson, we are going to see how to how to access a single resource from multiple threads

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or tasks by the help of a new text when using mutex.

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There are two functions or two API.

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We need we need the, um, the new tax give and the new tax take or the semaphores take and the semaphores

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give me Texas, that type of semaphore.

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So, um, I'm gonna come over here.

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This is my third one.

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You can think of the mutex as a key, a single key to the rest room or the toilet or the um the restroom.

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I know you get what I mean.

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So if you want to go to the restroom, you pick up the key and then you open the door.

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When you finish using it returned a key such that the next person can pick up the key.

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Open the door.

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And when different issues in it, they return.

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So we are going to use them.

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Ex semiformal take to take the key, so say ex semaphore, take does the name of the API.

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And this here takes the name off.

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The key name of the key is our new tax I.D..

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Over here.

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The new text we created in Cuba makes its code.

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You add new tax on those who control see to copy.

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And then I'm going to put this here and then we're going to add some delay here, such as it is a form

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of a timeout.

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So I'll say put Max DeLay and put Max DeLay means this is, um, infinite timeout.

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Meaning don't move on, too, until you get a key.

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You can put an amount of time here, such as fry them as such that if the key doesn't arrive in five,

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Emmis, break the door and enter.

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But if you put port max delay means if the key doesn't arrive.

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You cannot open the door.

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The door is still locked.

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But if we put something before, put an actual number here, which is not put to Max DeLay 10 M as hundred

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M as it means, if the key doesn't arrive within this time, you can go ahead and try to enter.

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Right.

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And you can think of the bathroom being that you got that you are the driver, the restroom being the

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are the driver.

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So wait, wait for infinite time until the key arrives before you can enter the restroom, which is

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the you are driver once you are done.

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You can return to key.

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We this uh this API should be you at take.

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I forgot to put a word take here.

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Once you are done you can return the key by saying x semaphore.

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You can give back the key x semaphore.

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Give like this and the name of the key is you are to new text Hondo.

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Right.

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And when given the key there is no time involved.

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So this is it.

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So the same thing is going to be done for our our threat to thread two would also need to take the same

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key.

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The key name is the same.

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And we say, wait two.

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The key arrives.

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Wait.

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An infinite amount of time once you are done.

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You can also return the key.

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The same key.

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Like this.

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OK.

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I hope you understand the analogy so we can build now and see what we have a quicker way here to build.

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It's built successfully.

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Click here to get it onto the board.

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It's download in.

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It's downloading.

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OK.

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It's, quote, onto the board.

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Click here to stop.

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OK, so now we can go to war to return to see.

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Select.

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I was to report from here.

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This one over here, then change the board bodyweight.

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It's the correct but rate.

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OK, now we can see the returns from third one greeting from threat to almost equal amount of threat

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one and three, two.

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In fact, they have equal amount of access to the U.

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S.

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So this is the beauty of new tax.

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And you apply the same method when dealing with an LCD screen.

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If we replace the you out with an LCD screen, let's say we wanted to send the same message onto the

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screen.

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We would need to just use the dramatics to do that.

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So, yeah, this is how we solve the multiple access to a single resource using a new text.

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If you have any questions, leave it in the questions and answers area.

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Right.

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So this saw there is the next lesson.