GmailをSMTPサーバとして利用する方法です。 openssl s_client -connect smtp.gmail.com:465 -crlf -ign_eof -ign_eofがないと、以下のエラーでRCPT TO後に死ぬ RENEGOTIATING 21874:error:1409E0E5:SSL routines:SSL3_WRITE_BYTES:ssl handshake failure:/SourceCache/OpenSSL098/OpenSSL098-50/src/ssl/s3_pkt.c:543: opensslでセッションを開始したあとの対話は以下のように進みます EHLO localhost #ユーザー入力 250-mx.google.com at your service, [106.138.98.200] 250-SIZE 35882577 250-8BI
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