Question

How to pass a pointer to pointer as argument to a functions in C

Answer 1

#include <stdio.h>
 
void f(int **value)  {
	printf("f() %d\n", **value);
	
	**value = 100;
}
   
int main() 
{ 
	int n = 99;
	int *p = &n;
	int **pp = &p;
     
	printf("main() 1: %d\n", **pp);
	
	f(pp);
	
	printf("main() 2: %d\n", **pp);
	
	return 0; 
}
 
 
 
/*
run:
 
main() 1: 99
f() 99
main() 2: 100
 
*/

 

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