VB.Net Download full webpage HTML

Code:
#include <iostream>
#include <cstring>
#include <curl/curl.h>
#include <vector>
#include <sys/types.h>
#include <sys/stat.h>
#include "gumbo.h"

using namespace std;

CURL *curl;
CURLcode res;

int i = 1;

string data;

vector<string> links;

static size_t callback(void *data, size_t size, size_t nmemb, void *pointer) {
    ( (string*)pointer)->append((char*)data, size * nmemb);
    return size * nmemb;
}

string ltrim(string s, const char* t = " \t\n\r\f\v"){
    s.erase(0, s.find_first_not_of(t));
    return s;
}
string rtrim(string s, const char* t = " \t\n\r\f\v"){
    s.erase(s.find_last_not_of(t) + 1);
    return s;
}
string trim(string s, const char* t = " \t\n\r\f\v"){
    return ltrim(rtrim(s, t), t);
}

void extract_links( GumboNode* node )
{
    GumboAttribute* detail;
    if (node->type != GUMBO_NODE_ELEMENT) {
        return;
    }
    if( node->v.element.tag == GUMBO_TAG_A &&
    (detail = gumbo_get_attribute(&node->v.element.attributes, "href"))){
        links.push_back( trim( detail->value ) );
    }
    GumboVector* children = &node->v.element.children;
    for (unsigned int i = 0; i < children->length; ++i) {
        extract_links(static_cast<GumboNode*>(children->data[i]));
    }
}

int initialize_curl( const char* url )
{
    curl_global_init(CURL_GLOBAL_ALL);
    curl = curl_easy_init();
    if(curl) {
        curl_easy_setopt(curl, CURLOPT_URL, url);
    	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, callback);
    	curl_easy_setopt(curl, CURLOPT_WRITEDATA, &data);
    	curl_easy_setopt(curl, CURLOPT_USERAGENT, "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.90 Safari/537.36");
    	curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        curl_easy_setopt(curl, CURLOPT_COOKIEFILE, "cookies.txt");
        curl_easy_setopt(curl, CURLOPT_COOKIEJAR, "cookies.txt");
        res = curl_easy_perform(curl);
        if(res != CURLE_OK) {
            curl_easy_strerror(res);
            return 1;
        }
        curl_easy_cleanup(curl);
    }
    return 0;
}
void write_to_html_out( const char* input, const char* filename )
{
    string core = "/home/user/Downloads";
    char buffer[260];
    FILE *pFile;
    if(strstr( filename, "http") == NULL ) {
        if( strstr( filename, "html") == NULL ) {
            string tempfile = filename;
            string outfile = tempfile.substr(0, tempfile.find_last_of("/") );
            outfile = core + outfile;
            mkdir(outfile.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
        }
    }
    sprintf( buffer, "%s%s", core.c_str(), filename );
    if ( ( pFile = fopen(buffer, "w+") ) != NULL) {
        fprintf(pFile, "%s", input );
        fclose(pFile);
    }
}

string replace_all(string str, const string& from, const string& to) {
    size_t start_pos = 0;
    while((start_pos = str.find(from, start_pos)) != std::string::npos) {
        str.replace(start_pos, from.length(), to);
        start_pos += to.length();
    }
    return str;
}

void cleanup() { data = ""; }

int main (int argc, char *argv[])
{
    string root_url = "http://www.thedraculasociety.org.uk";

    if( initialize_curl( root_url.c_str() ) == 0 )
    {
        GumboOutput* output = gumbo_parse(data.c_str());

        extract_links(output->root);

        write_to_html_out( data.c_str(), "/index.html" );

    	for(vector<int>::size_type i = 0; i != links.size(); i++)
    	{
            string url = root_url + links[i].c_str();

            cleanup( );

            printf("Grabbing link: %s\r\n", links[i].c_str() );

            if( initialize_curl( url.c_str() ) == 0 ) {

                GumboOutput* output = gumbo_parse(data.c_str());

                write_to_html_out( data.c_str(), links[i].c_str() );

                cleanup( );
            }
        }
        getchar( );
    }
    return 0;
}