39 lines
1.3 KiB
C
39 lines
1.3 KiB
C
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#include <stdio.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <wait.h>
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int main() {
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printf("Parent PID: [%d]\n", getpid()); // Initial parent
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if (fork() == 0) { // Forking child
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printf("Child PID: [%d]\n", getpid());
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int to_lowercase[2];
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pipe(to_lowercase);
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if (fork() == 0) { // Forking grandchild
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printf("Grandchild PID: [%d]\n", getpid());
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char output[100];
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read(to_lowercase[0], output, 100); // Reading from pipe
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close(to_lowercase[0]); // Closing read pipe
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for (int i = 0; i < 100; i++) { // Converting to lowercase using ASCII
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if (output[i] >= 'A' && output[i] <= 'Z') {
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output[i] += 32;
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}
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}
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printf("%s", output);
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printf("Grandchild PID: [%d]\n", getpid());
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exit(EXIT_SUCCESS);
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} else { // Child
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char input[100];
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fgets(input, 100, stdin); // Input
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write(to_lowercase[1], input, 100); // Writing to pipe
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close(to_lowercase[1]); // Closing write pipe
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wait(NULL);
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printf("Grandchild PID: [%d]\n", getpid());
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exit(EXIT_SUCCESS);
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}
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} else { // Parent
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wait(NULL);
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printf("Parent PID: [%d]\n", getpid());
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}
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exit(EXIT_SUCCESS);
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}
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