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You know, structure where we implement our function to actually function is especially important for

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us because it means that we can build a program in the host system and a call to our system runs a program

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just admitted into operating systems like Windows or Linux.

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How do you see in order to run a program in our system, we first focal process.

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And a red after we are in the process, we ask you to function to launch a specific program, to ask

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you to function, we will search the program with the help of the system on inculpate its instructions

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and a data to the USERSPACE.

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If we can find the program in the image.

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And at this point, the new process, we will be running just as we launched a specific program.

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All right, we start off with the user one program.

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As you can see, this is a user program in the last way to support we are currently returning from the

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work function as a new process.

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We're [REMOVED], so we enter if statement instead of printing message.

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What we are going to do is we are going to ask you to file.

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So we can function as good.

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And at this fire will be loaded into your airspace, which means all the code and data here will be

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replaced with the instructions and a data of the program, we will ask.

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It has not been in this case.

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As for the process which started the for cooperation, when it returns from the colonel, it will return

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to the part and wait for the new process to allow it.

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So here we change the message test process and that after we return from the wavefunction.

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So the general structure of the fork and weight operations are still the same as we talked about in

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the last structure.

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OK, the other part is done.

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Next, we move to a torn apart.

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So ask you to function is implemented in the process modu.

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Here you can see we do ask you to function, which takes two parameters, the current process and the

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filename, because we want to load the file in the memory and execute.

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We need to open the file on a rate data from it.

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So we define larible file, descriptor and size.

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Then they open fire on a check.

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The reason why do if they open fired, we do nothing.

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But as it is a process, otherwise, we initialize the user page with zero because we will copy the

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data of a new file to the user space another week as a file size after we get the file size where rates

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of our data to the buffer.

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Four hundred thousand.

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Remember the system.

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This is a big surprise of the user space.

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If the return value of the rate of file is a maximum value, the operation failed and we simply added

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out.

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OK, at this point, the data in the U.S.

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Space is replaced with this file.

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Also, don't forget to close the file.

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Since this is not the first time we run the process, we have the user data in the frame when we enter

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the Kermode.

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What do we want to do in this case is clear the trap frame and studied it, the default state, so we

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clear the trap frame and asset to our IP, our ISP, etc. to justify values.

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OK, after it is done, when we return to the other mode where we will get to the start of the program

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just as we launch the process for the first time.

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OK, that's it for the process.

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Montreal.

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In the sitcom Modu.

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We ask obscure function on a function such as cute.

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We retrieved the car and process, then we ask it to function and arguments are the process and the

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filename we passed from user program.

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Changes to checks in the system called function, and we are done to nothing.

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We are going to do is we are going to add to obscure function interlibrary.

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So interlibrary foder.

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We add actual function intercepts commodity.

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What defines Adobo as cute?

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Since it takes one parameter, we allocate eight by space on a stack, so we subtract out.

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So index for the obscure function is 11, so Waymouth, IEX 11.

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Then we cop his argument on a stack.

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On the move already, I have one indication that we have one argument that we save the price of the

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argument in register I sign.

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OK, we're into it.

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After we return from the colonel, we add our associate to restart Stack and then we simply return.

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Global obscure function on the Cisco module is done.

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Interlibrary had high profile, we had function as acute.

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OK, that's great syllabary file in the terminal.

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We go to Laborie Folger, Anderson Poultices Modu.

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Then they added in the lab of Rafael.

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We copies elaborate a file on the high profile.

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To the test folder.

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And the use of one, Fauja.

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Now, let's create a test that's been filed since, where we'll build a test to use a program, we need

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files such as library file to file the start up file Terlingua script and build a script.

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So we just copy them from user and product.

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In the immediacy of the Transport Act.

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But just Pariente test process starts.

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And it's up your script.

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We specify that the name of the to file is test not being.

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OK, all the files all prepared.

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That's both a test product, use a product on a product.

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OK, let's move to offset the image.

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Copies of test being file.

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So, Colonel, meanwhile.

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And a user tarping file.

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With this month's deportation.

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On the rent, a postscript.

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As you can see, test process starts on a test process access.

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You'll see it's a test process is running great.

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We are running the program in our operating system.