Leading period DATA 354 Enter mail, end with on a line by itself Hi dave -this message is a test of SMTP foo 250 VAA0771 Message accepted for delivery 最终信息 Hi dave this message is a test of smtp f。o9 Leading Period DATA 354 Enter mail, end with "." on a line by itself Hi dave - this message is a test of SMTP .. ..foo .. . 250 VAA0771 Message accepted for delivery • 最终信息: Hi dave - this message is a test of SMTP . .foo