44 lines
743 B
C
44 lines
743 B
C
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//
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// Written for Computer Networks and Systems lab classes
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// AUTHOR : Sergiusz Warga
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <unistd.h>
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int main() {
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int pipefd[2];
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if (pipe(pipefd) < 0) {
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fprintf(stderr, "Something went wrong!\n");
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return -1;
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}
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pid_t pid;
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pid = fork();
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if (pid == -1) { // If something went wrong.
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perror("Fork: ");
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exit(EXIT_FAILURE);
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}
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if (pid == 0) { // If this is a child process.
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dup2(pipefd[1], STDOUT_FILENO);
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execl("/usr/bin/cal", "cal", NULL);
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close(pipefd[1]);
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exit(EXIT_SUCCESS);
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}
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char buff[200] = {};
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while (read(pipefd[0], &buff, sizeof(buff)) > 0) {
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printf("%s", buff);
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}
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int status;
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wait(&status);
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return 0;
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}
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