37 lines
		
	
	
	
		
			655 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
	
		
			655 B
		
	
	
	
		
			C
		
	
	
	
	
	
| // init: The initial user-level program
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| 
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| #include "types.h"
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| #include "stat.h"
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| #include "user.h"
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| #include "fcntl.h"
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| 
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| char *sh_args[] = { "sh", 0 };
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| 
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| int
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| main(void)
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| {
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|   int pid, wpid;
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| 
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|   if(open("console", O_RDWR) < 0){
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|     mknod("console", 1, 1);
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|     open("console", O_RDWR);
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|   }
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|   dup(0);  // stdout
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|   dup(0);  // stderr
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| 
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|   for(;;){
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|     printf(1, "init: starting sh\n");
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|     pid = fork();
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|     if(pid < 0){
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|       printf(1, "init: fork failed\n");
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|       exit();
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|     }
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|     if(pid == 0){
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|       exec("sh", sh_args);
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|       printf(1, "init: exec sh failed\n");
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|       exit();
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|     }
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|     while((wpid=wait()) >= 0 && wpid != pid)
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|       printf(1, "zombie!\n");
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|   }
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| }
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