46 lines
928 B
C
46 lines
928 B
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <assert.h>
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#include <fcntl.h>
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#include <sys/wait.h>
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#include <sys/types.h>
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int main(int argc, char *argv[])
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{
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if (argc < 2)
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{
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printf("Usage: %s <file>\n", argv[0]);
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return EXIT_FAILURE;
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}
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int pip, fd[2], outfile, d;
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char buf;
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pip = pipe(fd);
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assert(pip != -1);
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pid_t p = fork();
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assert(p != -1);
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outfile = open(argv[1], O_WRONLY | O_CREAT, 0644);
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switch (p)
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{
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case 0:
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close(fd[0]);
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d = dup2(fd[1], 1);
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execl("/usr/bin/ls", "ls", "-i", "-l", "/tmp", NULL);
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close(fd[1]);
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exit(0);
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default:
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close(fd[1]);
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while (read(fd[0], &buf, sizeof(char)) > 0)
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{
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write(outfile, &buf, sizeof(char));
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}
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break;
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}
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close(outfile);
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return EXIT_SUCCESS;
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}
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