Sample code for 30+ languages & platforms
Unicode C++

POP3 over Multiple Hop SSH

Demonstrates how to read POP3 email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:
Application => ServerSSH1 => ServerSSH2 => POP3Server

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkSshW.h>
#include <CkMailManW.h>
#include <CkEmailW.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.

    CkSshW ssh1;

    // Connect directly to the 1st SSH server.
    success = ssh1.Connect(L"serverssh1.com",22);
    if (success == false) {
        wprintf(L"%s\n",ssh1.lastErrorText());
        return;
    }

    // Authenticate using login/password:
    success = ssh1.AuthenticatePw(L"ssh1Login",L"ssh1Password");
    if (success == false) {
        wprintf(L"%s\n",ssh1.lastErrorText());
        return;
    }

    // Connect through the 1st SSH connection to reach a 2nd SSH server.
    // Note: Any number of SSH connections may be simultaneously tunneled through a single
    // existing SSH connection.
    CkSshW ssh2;
    success = ssh2.ConnectThroughSsh(ssh1,L"serverssh2.com",22);
    if (success == false) {
        wprintf(L"%s\n",ssh2.lastErrorText());
        return;
    }

    // Authenticate with ssh2...
    success = ssh2.AuthenticatePw(L"ssh2Login",L"ssh2Password");
    if (success == false) {
        wprintf(L"%s\n",ssh2.lastErrorText());
        return;
    }

    CkMailManW mailman;

    // Tell the mailman object to connect to the POP3 server though the ssh2 tunnel (which itself is routed through ssh1).
    // The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => POP3Server
    success = mailman.UseSsh(ssh2);
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    // Set the POP3 server's hostname
    mailman.put_MailHost(L"pop.example.com");

    // Set the POP3 login/password.
    mailman.put_PopUsername(L"myLogin");
    mailman.put_PopPassword(L"myPassword");

    // Establish the POP3 connection through the ssh2 tunnel.
    success = mailman.Pop3BeginSession();
    if (success == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    // Get the number of messages in the mailbox.
    int numMessages = mailman.GetMailboxCount();

    CkEmailW email;
    int i = 1;
    while (i <= numMessages) {
        // Fetch by the message number (not by the UIDL)
        success = mailman.FetchOne(false,0,i,email);
        if (success == false) {
            wprintf(L"%s\n",mailman.lastErrorText());
            return;
        }

        wprintf(L"%s: %s\n\n",email.ck_from(),email.subject());

        i = i + 1;
    }

    // Close the connection with the POP3 server.  (This closes the tunnel through ssh2)
    // The connection with ssh2 is still alive, and may be used for more connections.
    success = mailman.Pop3EndSession();

    // Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
    // The connection with ssh1 is still alive, and may be used for more connections.

    ssh2.Disconnect();

    ssh1.Disconnect();
    }