39 lines
577 B
C
39 lines
577 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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#define BUF_SIZE 128
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int main(void){
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pid_t x, x1, x2, x3;
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int p[2];
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char buf;
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assert(pipe(p) != -1);
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x1 = fork();
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if (x1 == 0){
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x2=fork();
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if (x2 == 0){
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x = fork();
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if (x == 0){
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close(p[0]);
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dup2(p[1], 1);
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close(p[1]);
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printf("%d", getpid());
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}
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x3=fork();
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}
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sleep(1);
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}
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if (x1 > 0){
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close(p[1]);
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while(read(p[0], &buf, sizeof(char)) > 0)
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write(1, &buf, sizeof(char));
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}
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close(p[0]);
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printf("\n");
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return EXIT_SUCCESS;
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}
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