báo cáo bài tập nhập môn hệ điều hành lab 6

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<b>TRƯỜNG ĐẠI HỌC TÔN ĐỨC THẮNG KHOA CÔNG NGHỆ THÔNG TIN </b>

<b>BÁO CÁO BÀI TẬP NMHĐHHK2, 2022-2023</b>

<b>Lab 6Nhóm:</b> 10 <b>Tổ:</b> 02

Trần Tuấn Kiệt – (MSSV: 52300040)

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<b>Mục lục</b>

<b>……….</b>

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<b>A. PHẦN THỰC HÀNH</b>

<b>I. Unnamed pipe:</b>

1. The parent process of passing the first argument from argv [1] is an integer greater than 3 for the child process through Pipe. The child process receives, calculates the factorial number n! = 1*2*…* n and writes it to the pipe. The parent process of receiving and exporting data to the screen.

<b>A: Code Chương Trình</b>

#include <stdio.h>#include <stdlib.h>#include <unistd.h>

int factorial(int n) { int result = 1;

for (int i = 2; i <= n; i++) { result *= i;

} return result;}

int main(int argc, char *argv[]) { if (argc != 2) {

fprintf(stderr, "Usage: %s <number>\n", argv[0]); return EXIT_FAILURE;

}

int num = atoi(argv[1]);

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pid_t pid = fork(); if (pid < 0) { perror("fork"); return EXIT_FAILURE; }

if (pid == 0) { // Tiến trình con close(pipefd[0]);

int result = factorial(num);

if (write(pipefd[1], &result, sizeof(result)) == -1) { perror("write");

return EXIT_FAILURE; }

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close(pipefd[1]); exit(EXIT_SUCCESS); } else { // Tiến trình cha close(pipefd[1]);

int result;

if (read(pipefd[0], &result, sizeof(result)) == -1) { perror("read");

return EXIT_FAILURE; }

close(pipefd[0]);

printf("Factorial of %d is: %d\n", num, result); }

return EXIT_SUCCESS;}

<b>B: Kết Quả Demo</b>

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2. The parent process reads two integers and one operation +, -, *, / and passes all to the child process. The child process calculates the result and returns it to the parent process. The parent process writes the result to a file.

<b>A: Code Chương Trình</b>

#include <stdio.h>#include <unistd.h>#include <stdlib.h>#include <sys/wait.h>int main(int argc, char *argv[]) { if (argc != 5) {

fprintf(stderr, "Usage: %s <num1> <num2> <operation> <output_filename>\nNote that multiplication will be written as '*' to avoid the machine misinterpreting it as another function\n", argv[0]);

return EXIT_FAILURE; }

int num1 = atoi(argv[1]); int num2 = atoi(argv[2]); char op = argv[3][0];

char* output_filename = argv[4];

int pipefd[2]; pid_t pid;

if (pipe(pipefd) == -1) { perror("pipe"); return EXIT_FAILURE; }

pid = fork(); if (pid < 0) { perror("fork"); return EXIT_FAILURE; }

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if (pid == 0) { // Tiến trình con close(pipefd[0]); int result; switch (op) { case '+':

result = num1 + num2; break;

fprintf(stderr, "Error: Division by zero\n"); close(pipefd[1]);

exit(EXIT_FAILURE); }

break; default:

fprintf(stderr, "Error: Invalid operation\n"); close(pipefd[1]);

exit(EXIT_FAILURE); }

FILE *file = fopen(output_filename, "w"); if (file == NULL) {

perror("fopen"); close(pipefd[1]); exit(EXIT_FAILURE); }

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fprintf(file, "%d %c %d = %d\n", num1, op, num2, result); fclose(file);

close(pipefd[1]); exit(EXIT_SUCCESS); } else { // Tiến trình cha close(pipefd[1]);

wait(NULL); // Đợi tiến trình con hồn thành

printf("Result has been written to '%s'\n", output_filename); }

return EXIT_SUCCESS;}

<b>B: Kết Quả Demo</b>

<b>II. Named pipe:</b>

<b>Slove 2 above problems with named pipe.1.</b>

<b>A: Code Chương Trình</b>

#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <sys/wait.h>

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int factorial(int n) {if (n == 0) return 1;

return n * factorial(n - 1);}

int main(int argc, char *argv[]) {if (argc != 2) {

fprintf(stderr, "Usage: %s <number>\n", argv[0]); return 1;

if (pid == 0) { // Child process int fd = open(fifo_name, O_WRONLY); if (fd == -1) {

perror("open"); return 1; }

int result = factorial(num); write(fd, &result, sizeof(result)); close(fd);

exit(0);

} else { // Parent process

int fd = open(fifo_name, O_RDONLY); if (fd == -1) {

perror("open"); return 1;

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} int result;

read(fd, &result, sizeof(result));

printf("Factorial of %d is: %d\n", num, result); close(fd);

wait(NULL);}

unlink(fifo_name); // Remove the FIFOreturn 0;

#define FIFO_FILE "/tmp/calculator_fifo"

int main() {

// Create named pipemkfifo(FIFO_FILE, 0666);

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pid_t pid = fork();if (pid == -1) { perror("fork"); exit(EXIT_FAILURE);

// Receive data from parent process int num1, num2;

char operation;

read(fd, &num1, sizeof(num1)); read(fd, &num2, sizeof(num2)); read(fd, &operation, sizeof(operation));

// Calculate result int result; switch (operation) { case '+':

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result = num1 + num2; break;

fprintf(stderr, "Error: Division by zero\n"); exit(EXIT_FAILURE);

} break; default:

fprintf(stderr, "Error: Invalid operation\n"); exit(EXIT_FAILURE);

}

// Close pipe close(fd);

// Open pipe for writing

fd = open(FIFO_FILE, O_WRONLY);

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if (fd == -1) { perror("open"); exit(EXIT_FAILURE); }

// Send result back to parent process write(fd, &result, sizeof(result));

// Close pipe close(fd);

exit(EXIT_SUCCESS);} else { // Parent process // Open pipe for writing

int fd = open(FIFO_FILE, O_WRONLY); if (fd == -1) {

perror("open"); exit(EXIT_FAILURE); }

// Get input from user int num1, num2; char operation;

printf("Enter two integers and an operation (+, -, *, /): "); scanf("%d %d %c", &num1, &num2, &operation);

// Send data to child process

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write(fd, &num1, sizeof(num1)); write(fd, &num2, sizeof(num2)); write(fd, &operation, sizeof(operation));

// Close pipe close(fd);

// Open pipe for reading

fd = open(FIFO_FILE, O_RDONLY); if (fd == -1) {

perror("open"); exit(EXIT_FAILURE); }

// Receive result from child process int result;

read(fd, &result, sizeof(result));

// Close pipe close(fd);

// Write result to file

FILE *file = fopen("result.txt", "w"); if (file == NULL) {

perror("fopen"); exit(EXIT_FAILURE);

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<b>B: Kết Quả Demo</b>

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