(C++) MX Lookup Mail Server Domain by Email Address

How to find the mail server for a given email address. Returns the domain name of the primary mail server.

Note: This example requires Chilkat v11.0.0 or greater.

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#include <CkDns.h>
#include <CkJsonObject.h>

void ChilkatSample(void)
    {
    bool success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkDns dns;
    CkJsonObject json;

    const char *emailAddr = "bob@example.com";

    // This gets all MX domains for an email address.  (Typically one domain.)
    // The preferred domain will be at index 0 (see below).
    success = dns.Query("MX",emailAddr,json);
    if (success == false) {
        std::cout << dns.lastErrorText() << "\r\n";
        return;
    }

    int i = 0;
    int count_i = json.SizeOfArray("answer.mx");
    while (i < count_i) {
        json.put_I(i);
        const char *domain = json.stringOf("answer.mx[i].domain");
        std::cout << domain << "\r\n";
        i = i + 1;
    }
    }