The free() Call

Let's learn about the `free` call in this lesson!

As it turns out, allocating memory is the easy part of the equation; knowing when, how, and even if to free memory is the hard part. To free heap memory that is no longer in use, programmers simply call free():

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#include<stdio.h>
int main() {
    int *x = malloc(10 * sizeof(int));
     printf("%d\n", sizeof(x));
    //...
    free(x);
    return 0;
}

The routine takes one argument, a pointer returned by malloc(). Thus, you might notice, the size of the allocated region is not passed in by the user, and must be tracked by the memory-allocation library itself.

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