104 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			104 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* test 4 */
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| 
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| #include <sys/types.h>
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| #include <sys/wait.h>
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| #include <fcntl.h>
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| #include <signal.h>
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| #include <stdlib.h>
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| #include <unistd.h>
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| #include <stdio.h>
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| #include <string.h>
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| 
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| pid_t pid0, pid1, pid2, pid3;
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| int s, i, fd, nextb, errct = 0;
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| char *tempfile = "test4.temp";
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| char buf[1024];
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| extern int errno;
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| 
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| _PROTOTYPE(int main, (void));
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| _PROTOTYPE(void subr, (void));
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| _PROTOTYPE(void nofork, (void));
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| _PROTOTYPE(void quit, (void));
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| 
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| int main()
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| {
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|   int k;
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| 
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|   printf("Test  4 ");
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|   fflush(stdout);		/* have to flush for child's benefit */
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| 
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|   system("rm -rf DIR_04; mkdir DIR_04");
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|   chdir("DIR_04");
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| 
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|   creat(tempfile, 0777);
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|   for (k = 0; k < 20; k++) {
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| 	subr();
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|   }
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|   unlink(tempfile);
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|   quit();
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|   return(-1);			/* impossible */
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| }
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| 
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| void subr()
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| {
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|   if ( (pid0 = fork()) != 0) {
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| 	/* Parent 0 */
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| 	if (pid0 < 0) nofork();
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| 	if ( (pid1 = fork()) != 0) {
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| 		/* Parent 1 */
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| 		if (pid1 < 0) nofork();
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| 		if ( (pid2 = fork()) != 0) {
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| 			/* Parent 2 */
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| 			if (pid2 < 0) nofork();
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| 			if ( (pid3 = fork()) != 0) {
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| 				/* Parent 3 */
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| 				if (pid3 < 0) nofork();
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| 				for (i = 0; i < 10000; i++);
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| 				kill(pid2, 9);
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| 				kill(pid1, 9);
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| 				kill(pid0, 9);
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| 				wait(&s);
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| 				wait(&s);
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| 				wait(&s);
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| 				wait(&s);
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| 			} else {
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| 				fd = open(tempfile, O_RDONLY);
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| 				lseek(fd, 20480L * nextb, 0);
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| 				for (i = 0; i < 10; i++) read(fd, buf, 1024);
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| 				nextb++;
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| 				close(fd);
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| 				exit(0);
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| 			}
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| 		} else {
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| 			while (1) getpid();
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| 		}
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| 	} else {
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| 		while (1) getpid();
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| 	}
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|   } else {
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| 	while (1) getpid();
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|   }
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| }
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| 
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| void nofork()
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| {
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|   int e = errno;
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|   printf("Fork failed: %s (%d)\n",strerror(e),e);
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|   exit(1);
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| }
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| 
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| void quit()
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| {
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| 
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|   chdir("..");
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|   system("rm -rf DIR*");
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| 
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|   if (errct == 0) {
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| 	printf("ok\n");
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| 	exit(0);
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|   } else {
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| 	printf("%d errors\n", errct);
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| 	exit(1);
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|   }
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| }
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