Unicode C

DNS Query MX Records

See more DNS Examples

Shows how to perform a DNS query to retrieve MX records.

Note: This example requires Chilkat v9.5.0.96 or later.

Unicode C

#include <C_CkDnsW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkDnsW dns;
    HCkJsonObjectW json;
    const wchar_t *name;
    int ttl;
    int pref;
    const wchar_t *domain;
    int i;
    int count_i;

    success = FALSE;

    dns = CkDnsW_Create();

    json = CkJsonObjectW_Create();
    CkJsonObjectW_putEmitCompact(json,FALSE);

    success = CkDnsW_Query(dns,L"MX",L"somebody@gmail.com",json);
    if (success == FALSE) {
        wprintf(L"%s\n",CkDnsW_lastErrorText(dns));
        CkDnsW_Dispose(dns);
        CkJsonObjectW_Dispose(json);
        return;
    }

    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    // Sample response.
    // Parsing code below..

    // -------------------------------------------------------------------------------
    // Note: Chilkat will return the results sorted by "pref" from lowest to highest.
    // -------------------------------------------------------------------------------

    // {
    //   "answer": {
    //     "mx": [
    //       {
    //         "name": "gmail.com",
    //         "ttl": 491,
    //         "pref": 5,
    //         "domain": "gmail-smtp-in.l.google.com"
    //       },
    //       {
    //         "name": "gmail.com",
    //         "ttl": 491,
    //         "pref": 10,
    //         "domain": "alt1.gmail-smtp-in.l.google.com"
    //       },
    //       {
    //         "name": "gmail.com",
    //         "ttl": 491,
    //         "pref": 20,
    //         "domain": "alt2.gmail-smtp-in.l.google.com"
    //       },
    //       {
    //         "name": "gmail.com",
    //         "ttl": 491,
    //         "pref": 30,
    //         "domain": "alt3.gmail-smtp-in.l.google.com"
    //       },
    //       {
    //         "name": "gmail.com",
    //         "ttl": 491,
    //         "pref": 40,
    //         "domain": "alt4.gmail-smtp-in.l.google.com"
    //       }
    //     ]
    //   }
    // }

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    i = 0;
    count_i = CkJsonObjectW_SizeOfArray(json,L"answer.mx");
    while (i < count_i) {
        CkJsonObjectW_putI(json,i);
        name = CkJsonObjectW_stringOf(json,L"answer.mx[i].name");
        ttl = CkJsonObjectW_IntOf(json,L"answer.mx[i].ttl");
        pref = CkJsonObjectW_IntOf(json,L"answer.mx[i].pref");
        domain = CkJsonObjectW_stringOf(json,L"answer.mx[i].domain");
        i = i + 1;
    }



    CkDnsW_Dispose(dns);
    CkJsonObjectW_Dispose(json);

    }