Malloc or normal array definition?

Question

When shall i use malloc instead of normal array definition in C?

I can't understand the difference between:

int a[3]={1,2,3}
int array[sizeof(a)/sizeof(int)]

and:

array=(int *)malloc(sizeof(int)*sizeof(a));

Answer 1

In general, use malloc() when:

• the array is too large to be placed on the stack
• the lifetime of the array must outlive the scope where it is created

Otherwise, use a stack allocated array.