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Why does this code that uses a pointer-to-pointer-to-int segfault?
+1
−3
Hello folks, can someone resolve this seg fault with me please, i can't find the error where it occur. Thank you.
#include <stdlib.h>
#include <stdio.h>
int ft_ultimate_range(int **range, int min, int max)
{
int lentgh;
int i;
int mi;
mi = min;
lentgh = max - min;
if (min >= max)
{
// *range = NULL;
return (0);
}
*range = malloc(sizeof(int) * lentgh);
if(!range)
{
return 0;
}
i = 0;
while (min < max)
{
range[0][i] = mi;
i++;
mi++;
}
return (i);
}
int main()
{
int i = 0;
int min = 5;
int max = 19;
int **range = 0;
int ptr = ft_ultimate_range(range, min, max);`
while(i < max - min)
{
printf("%d\n", ptr);
i++;
}
return (0);
}
1 answer
+3
−0
Bugs:
-
int **range = 0;
should beint *range;
and then call the function likeft_ultimate_range(&range, min, max);
. That's the whole reason the parameter is pointer-to-pointer, so that you can return a malloc:ed pointer through a parameter. -
while (min < max)
neither min nor max change inside the loop. This is the reason for the seg fault, becausei
keeps increasing and eventually you accessrange
out of bounds. -
while(i < max - min)
in main() doesn't make any sense, you can simply return that loop. You probably intended to do something with the allocated data instead here?
Minor stuff:
- There's no obvious reason why you can't simply return the pointer from the function. It then becomes
int* ft_ultimate_range(int min, int max)
and all the pointer-to-pointer syntax can be removed. - Don't give a plain
int
the nameptr
... -
lentgh
typo ->length
3 comment threads