93 lines
1.6 KiB
C
Executable File
93 lines
1.6 KiB
C
Executable File
#include <unistd.h>
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#include <sys/wait.h>
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#include <sys/types.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <fcntl.h>
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enum
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{
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ACCESS_FILE = 0660
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};
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int
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main(int argc, char **argv)
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{
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char *cmd1 = argv[1];
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char *cmd2 = argv[2];
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char *cmd3 = argv[3];
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char *file1 = argv[4];
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char *file2 = argv[5];
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int fd1 = open(file1, O_RDONLY);
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int fd2 = open(file2, O_WRONLY | O_APPEND | O_CREAT, ACCESS_FILE);
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if (fd1 == -1 || fd2 == -1) {
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exit(1);
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}
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int fd[2];
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if (pipe(fd) == -1) {
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return 1;
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}
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pid_t pid = fork();
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if (pid == 0) {
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close(fd[0]);
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if (dup2(fd[1], 1) == -1) {
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_exit(1);
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}
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pid = fork();
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if (pid == 0) {
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if (dup2(fd1, 0) == -1) {
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_exit(1);
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}
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execlp(cmd1, cmd1, NULL);
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_exit(1);
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} else if (pid == -1) {
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exit(1);
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}
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int status;
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wait(&status);
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if (WIFEXITED(status) && !WEXITSTATUS(status)) {
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pid = fork();
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if (pid == 0) {
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execlp(cmd2, cmd2, NULL);
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_exit(1);
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} else if (pid == -1) {
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exit(1);
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}
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wait(NULL);
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}
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_exit(0);
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} else if (pid == -1) {
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exit(1);
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}
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close(fd[1]);
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pid = fork();
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if (pid == 0) {
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if (dup2(fd2, 1) == -1 || dup2(fd[0], 0)) {
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_exit(1);
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}
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execlp(cmd3, cmd3, NULL);
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_exit(1);
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} else if (pid == -1) {
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exit(1);
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}
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close(fd[0]);
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while (wait(NULL) != -1)
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;
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return 0;
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}
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