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1 // init: The initial user-level program
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2
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3 #include "types.h"
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4 #include "stat.h"
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5 #include "user.h"
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6 #include "fcntl.h"
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7
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8 char *argv[] = { "sh", 0 };
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9
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10 int
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11 main(void)
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12 {
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13 int pid, wpid;
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14
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15 if(open("console", O_RDWR) < 0){
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16 mknod("console", 1, 1);
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17 open("console", O_RDWR);
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18 }
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19 dup(0); // stdout
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20 dup(0); // stderr
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21
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22 for(;;){
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23 printf(1, "init: starting sh\n");
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24 pid = fork();
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25 if(pid < 0){
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26 printf(1, "init: fork failed\n");
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27 exit();
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28 }
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29 if(pid == 0){
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30 exec("sh", argv);
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31 printf(1, "init: exec sh failed\n");
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32 exit();
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33 }
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34 while((wpid=wait()) >= 0 && wpid != pid)
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35 printf(1, "zombie!\n");
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36 }
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37 }
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