Question

Before C99 programmers were obliged to define all arrays with fixed sizes that were known at compile time. How did people manage to create and access structures that behaved like arrays but whose sizes were not known until runtime?

Answer 1

With the use of malloc(3) and free(3) to do dynamic memory management. It’s still done today.

void f(int n)
{
  int *nInts = malloc(n * sizeof(int));

  /* do stuff with 'nInts' */

  free(nInts);
}