57 lines
1.3 KiB
C
57 lines
1.3 KiB
C
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//
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// Wrote 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 <sys/types.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <signal.h>
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void parent_before_child() {
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pid_t pid;
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printf("parent_before_child()\n");
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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 parent process.
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printf("I am a parent.\n");
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kill(getpid(), SIGKILL);
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} else {
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sleep(1);
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printf("I am a child\n"); // This line will not be printed, as (usually) parent process will finish
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// its execution in less than 1 second.
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}
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}
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void child_before_parent() {
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pid_t pid;
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printf("child_before_parent()\n");
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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 parent process.
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printf("I am a child.\n");
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kill(getpid(), SIGKILL);
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} else {
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sleep(1);
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printf("I am a parent.\n");
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}
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}
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int main() {
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pid_t pid;
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pid = fork();
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if (pid == 0) {
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child_before_parent();
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sleep(1);
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parent_before_child();
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sleep(1);
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}
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sleep(5);
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return 0;
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}
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