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POP3 GMail XOAUTH2 Authentication

See more GMail SMTP/IMAP/POP Examples

Demonstrates using OAuth2 authentication with pop.gmail.com.

Note: This example requires Chilkat v9.5.0.83 or greater.

Chilkat C Downloads

C
#include <C_CkMailMan.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkMailMan mailman;
    HCkJsonObject jsonToken;
    int numEmails;

    success = FALSE;

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

    mailman = CkMailMan_Create();

    CkMailMan_putMailHost(mailman,"pop.gmail.com");
    CkMailMan_putMailPort(mailman,995);
    CkMailMan_putPopSsl(mailman,TRUE);

    CkMailMan_putPopUsername(mailman,"my_account@gmail.com");

    // If using OAuth2 authentication, leave the password empty.
    CkMailMan_putPopPassword(mailman,"");

    // Load our previously obtained OAuth2 access token.
    // See Getting a GMail POP3 OAuth2 Access Token
    jsonToken = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(jsonToken,"qa_data/tokens/gmail_pop3.json");
    if (success == FALSE) {
        printf("%s\n",CkJsonObject_lastErrorText(jsonToken));
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    CkMailMan_putOAuth2AccessToken(mailman,CkJsonObject_stringOf(jsonToken,"access_token"));

    // Make the TLS connection to the POP3 server.
    success = CkMailMan_Pop3Connect(mailman);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    // Authenticate..
    success = CkMailMan_Pop3Authenticate(mailman);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    // Find out how many emails are on the server..
    numEmails = CkMailMan_CheckMail(mailman);
    if (numEmails < 0) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    // Examine the POP3 session log:
    printf("%s\n",CkMailMan_pop3SessionLog(mailman));

    // The POP3 session log will look something like this:

    // **** Connected to pop.gmail.com:995
    // < +OK Gpop ready for requests from 87.9.200.42 l16mb86351205iok
    // > AUTH XOAUTH2 dXNlcj1....VaMDJFAQE=
    // < +OK Welcome.
    // > STAT
    // < +OK 301 1627357
    // 
    // -- Finished.

    // End the POP3 session and close the connection to the GMail server.
    success = CkMailMan_Pop3EndSession(mailman);
    if (success != TRUE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    printf("-- Finished.\n");


    CkMailMan_Dispose(mailman);
    CkJsonObject_Dispose(jsonToken);

    }