VMime 介绍
VMime 是一个开源的用于处理电子邮件的 C++ 类库，支持 IMAP, POP 和 SMTP.
示例代码：
vmime::utility::url url(” smtp ://smtp.gmail.com”);
vmime::ref tr = session->getTransport(url);
tr- >setProperty(“connection.tls”, true);
tr->setProperty(“auth.username”, “gmail-login”);
tr->setProperty(“auth.password”, “gmail-password”);
tr->setProperty(“options.need-authentication”, true);
tr->setCertificateVerifier(yourCertificateVerifier);