Next Spaceship

Driving into future...

Obtain the Title of a Website

| Comments

The idea is to retrieve the html file of the website and parse it to find the content between <title> and </title>.

To get the html file, we need a library in C++, as the standard library has no such functions. I choose the libcurl library, and you can download it here:

To parse the html file, I use the regular expression library, which is based on GNU systems.

Here is my code:

``` c Get The Title Of A Website #include #include #include <curl/curl.h> #include #include

//Created by Leon // //Mar, 21, 2011

FILE *fin; FILE *ftmp; FILE *fout;

size_t write_data (void *buffer, size_t size, size_t nmemb, void *userp) { return size * nmemb; }

int main (void) { CURL *curl; CURLcode res;

fin = fopen ("in.txt", "r");
ftmp = fopen("tmp.txt", "w");
fout = fopen("out.txt", "w");
curl = curl_easy_init();

if(curl) {
    printf("Got easy handle...n");
    curl_easy_setopt(curl, CURLOPT_URL, "");
    //curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, ftmp);
    //curl_easy_setopt(curl, CURLOPT_PROXY, "");
    //curl_easy_setopt(curl, CURLOPT_PROXYUSERPWD, "user:pwd");
    printf("Options is set.n");
    res = curl_easy_perform(curl);
    ftmp = fopen ("tmp.txt", "rb");
    if (NULL == ftmp) {
        fputs ("File error", stderr);
        exit (1);
    // Obtain file size:
    fseek (ftmp, 0, SEEK_END);
    long lSize = ftell (ftmp);
    rewind (ftmp);
    // Allocate memory to contain the whole file:
    char *buffer;
    buffer = (char *) malloc (sizeof(char) * lSize);
    if (NULL == buffer) {
        fputs ("Memory error", stderr);
        exit (2);
    // Copy the file into the buffer:
    size_t result;
    result = fread (buffer, 1, lSize, ftmp);
    if (result != lSize) {
        fputs ("Reading error", stderr);
        exit (3);
    // Regular expression compilation
    regex_t compiled;
    int res = regcomp (&compiled, "<title>\([^<]*\)</title>", REG_ICASE);
    if (0 != res) {
        fputs ("Regular expression compilation error.", stderr);
        exit (4);
    // Regular expression match
    regmatch_t matchptr[2];
    char err_msg[80];
    res = regexec (&compiled, buffer, 2, matchptr, 0);
    if (0 != res) {
        regerror(res, &compiled, err_msg, 80);
        printf("%sn", err_msg);
        exit (5);
    char *title = (char *)malloc(sizeof(char) * (matchptr[1].rm_eo - matchptr[1].rm_so) + 1);
    strncpy (title, buffer + matchptr[1].rm_so, matchptr[1].rm_eo - matchptr[1].rm_so);
    printf("%sn", title);
    fprintf(fout, "%sn", title);
    regfree (&compiled);
    free (buffer);
    /* always cleanup */
return 0; } ```