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In this example, the function f() is passed a const char pointer. It then typecasts the const specification away and proceeds to modify the contents.

void f(char const *str, int slen) {
   char *p = const_cast<char*>(str);
   int i;
   for (i = 0; i < slen && str[i]; i++) {
      if (str[i] != ' ') *p++ = str[i];
   }
}

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In this compliant solution, the function f is passed a non-const char pointer. The calling function must ensure that the null-terminated byte string passed to the function is not const by making a copy of the string or by other means.

void f(char *str, int slen) {
   char *p = str;
   int i;
   for (i = 0; i < slen && str[i]; i++) {
      if (str[i] != ' ') *p++ = str[i];
   }
}

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In this example, a const int array vals is declared, and then its content is modified by calling memset with the function, leading to values of 0 in the vals array.

int const vals[] = {3, 4, 5};
memset((int*) vals, 0, sizeof(vals));

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If the intention is to allow the array values to be modified, do not declare the array as const.

int vals[] = {3, 4, 5};
memset(vals, 0, sizeof(vals));

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