(C) Verify Email Recipients

A way to possibly determine valid/invalid email addresses. I would recommend being very careful about doing this because your IP address may be flagged as a potential spammer by the mail server (because you are probing for valid/invalid email addresses). This Chilkat functionality existed for many years, before this kind of activity became a problem. The functionality remains only because it is useful for some to test with their own SMTP servers.

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#include <C_CkMailMan.h>
#include <C_CkEmail.h>
#include <C_CkStringArray.h>

void ChilkatSample(void)
    {
    HCkMailMan mailman;
    HCkEmail email;
    BOOL success;
    HCkStringArray badAddrs;
    int i;

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

    mailman = CkMailMan_Create();

    // SMTP connection settings...
    CkMailMan_putSmtpHost(mailman,"smtp.example.com");
    CkMailMan_putSmtpUsername(mailman,"MY_SMTP_USERNAME");
    CkMailMan_putSmtpPassword(mailman,"MY_SMTP_PASSWORD");
    CkMailMan_putSmtpSsl(mailman,TRUE);
    CkMailMan_putSmtpPort(mailman,465);

    // Create a new email object
    email = CkEmail_Create();

    CkEmail_putSubject(email,"This is a test");
    CkEmail_putBody(email,"This is a test");
    CkEmail_putFrom(email,"myemail@example.com");
    success = CkEmail_AddTo(email,"person1","person1@example.com");
    success = CkEmail_AddTo(email,"person2","person2@example.com");
    success = CkEmail_AddTo(email,"person3","person3@example.com");
    // The SMTP server smtp.example.com won't know anything about an email address @somewhere_else.com
    success = CkEmail_AddTo(email,"person3","person4@somewhere_else.com");
    // ...

    // Verify recipients.
    // **** See the warning about using this API method in the description above.
    // (An SMTP server only knows valid email address for its own domain.  For example,
    // smtp.example.com *may* only know if person1@example.com is valid or invalid, but does
    // not know anything about the validity of email addresses having other domains.)
    badAddrs = CkStringArray_Create();
    success = CkMailMan_VerifyRecips(mailman,email,badAddrs);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        CkEmail_Dispose(email);
        CkStringArray_Dispose(badAddrs);
        return;
    }

    i = 0;
    while (i < CkStringArray_getCount(badAddrs)) {
        printf("%s\n",CkStringArray_getString(badAddrs,i));
        i = i + 1;
    }

    printf("done.\n");


    CkMailMan_Dispose(mailman);
    CkEmail_Dispose(email);
    CkStringArray_Dispose(badAddrs);

    }