39 lines
1.4 KiB
Markdown
39 lines
1.4 KiB
Markdown
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# Topic 3 – More forking
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## Task 1
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The main program creates one child process. The offspring is supposed to write numbers from 1 to 10 (every second) to the screen.
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The parent process should wait for the child process to finish and then output the message "END OF WORK"
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man 3 sleep
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man 2 wait
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## Task 2
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The main program generates two random integers:
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a - from the range 0...10
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b - from the range 20...30
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Then it creates a child process.
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The child process calculates the sum of a+b values and returns it as its exit status.
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The parent process waits for the child process to finish calculating, receives its execution status, and displays returned sum.
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man 2 exit
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man 2 wait
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Please read the description of WEXITSTATUS macro carefully.
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## Task 3
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The main program allocates a 1000000-element integer array on the heap (free-store)
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Then it fills it with random values from the range 0....100
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After preparing the array it creates 10 child processes. The task of each of the child processes is to determine the average value of the array fragment (rounded to the nearest integer):
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descendant 0 - from index 0 to 99999
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descendant 1 - from index 100000 to 199999
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descendant 2 - from index 200000 to 299999
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...
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The parent process waits for the descendant processes to complete their calculations and then determines the average value of the array elements based on the obtained partial averages.
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