[v0id]

In what way doesn't it work?

I've made an example. It shows how to re-allocate some already allocated space.

int row_size = 5;
int *row = (int *)malloc(sizeof(int) * row_size);

*(row+0) = 1;
*(row+1) = 4;
*(row+2) = 5;
*(row+3) = 2;
*(row+4) = 4;

row_size++;
row = (int *)realloc(row, sizeof(int) * row_size);

// After the re-allocation, we can now fill index five, too
*(row+5) = 6;