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Hello and welcome to the political walkthrough on multiprocessor control.

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Let's open this project now.

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We are going to build it and run it.

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So first we copy the path to this project and then we open our activity for native tools command from.

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And then we navigate to the folder issue of yes, copy.

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And Randy Cohen basket.

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Now he has finished compiling building we can run by.

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Pressing internal, and you can see that in the shellcode has.

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But that message box with a message.

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Hello from crack militants dot com.

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And you can see there's also output on the terminal showing us the handle to the lock.

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64.

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And the Trek creator in running.

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So just open the source code and try to follow along.

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See where it is coming from.

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So the first message is sixty four is coming from.

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From here.

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Sixty four and then the second message trick creator and running is coming from here.

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Trade created and rainy.

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So now let us try to run the same process again a second time and see whether he succeeds, so we'll

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copy the top one more time and open another access before any DevTools command prompt.

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Navigate to the same folder and run the same program again.

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And you see, he says, new processes.

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The night is already running in memory so that it's coming from here.

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So when you try to run the process, a second time is trying to create another lock.

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So what happens is you come here and you start the program, you will come here, you will again call

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this function is process running and pass it in a type of lock that you want to to use in this case,

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mutex.

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So you come here to the function is process running, and he receives the permit mutex and over here

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tests.

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So your control method is mutates.

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So this is true.

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So you would try to create another lock, but by using the same controller name as the first, yeah,

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first process.

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But he feels there you will get an error.

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So the error here is error already exists.

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And because of that, you will close a handle, so it will return true.

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So the default is is process running should be followed by here because you get the error or the ax.

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So this is set to true.

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So this true is being written and then he returns to the caller over here.

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He returns to the caller over here.

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This is true.

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So if it's true, he would bring a message process is denied.

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It is already running in memory.

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And then he will close in a main function by returning zero.

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So it's how it works.

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So we can also check my writing process had canal.

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And you can search you can search for the handle by clicking on this, find Hindu.

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And you say here we look for our name.

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Have a look, which is here.

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My luck.

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So here we look for my luck.

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Fine.

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And you see the tiniest mutant also known as mutex.

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And this is the name space for our luck.

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So that is why second process feels to run because the logging was already in place.

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And that is not true.

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The second one.

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So we change this to say I'm a foreigner.

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Semaphore, as you will recall, Semaphore is the one off the thanks of luck you find here.

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So we save our source code and we.

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Close this first one, and now we're going to rebuild by Colleen screaming again.

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And now running again.

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And we try to open another instance.

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From another time and again, he feels.

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All right, this time now we check the process hacker.

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Research for my blog and you find now is the time this has been changed to Semaphore.

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All right.

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So he's working.

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Now that is try the next one, which is the event, so come back down here.

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Hey, chief, these two event

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safe?

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Yeah, cool.

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And then recompile.

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And then running again.

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And now go to the different am known and try to run a second time and again, he feels.

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So he is working this two hour namespace, our lock files and click again and this time Typekit event.

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So that is what he uses even.

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Because we are using this create even API.

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They aren't going to use him or create.

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Maybe he wanted to create a semaphore lock.

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We use create him out for API.

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So now we know we're going to try new pipes.

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So let us change this to name by name by save it and then.

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Close the first program.

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Now the rebuilt again.

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Then we run it.

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It is running now, and we go to our second terminal and we run again.

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He tried to move again and he fears again.

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So he's walking.

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So we go back to our find handles and click on Find I'm.

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And this time you find it.

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Is this file so named fight with a kind of virtual file, which is in memory?

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It is.

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Purpose is to do in the process communication, but you are using it in this example as kind of lock.

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So this is the how we can control how a number of processes running memory by using this lock.

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So that's all for this session.

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Thank you for watching.