Question

If a constant is declared like this

const char   *http_range;

Then how can I write the content or the value of it in a text file? Could you please show me with syntax?

Answer 1

First, that is not “a constant”. It’s a pointer to constant character data, i.e. a pointer to a read-only string. You can change the pointer, but you can’t change the data it’s pointing at. For example:

FILE *out;
const char *http_range = "Accept: text/*;q=0.3, text/html;q=0.7";

if ((out = fopen("textfile.txt", "w")) != NULL)
{
  fprintf(out, "the range is '%s'\n", http_range);
  fclose(out);
}

Note that the above is in C, your question is weirdly double-tagged so I picked C.