RFC 1725:Post Office Protocol - Version 3
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requirement


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... number of messages in the maildrop, a single space, and the size of the maildrop in octets. This memo makes no requirement on what follows the maildrop size. Minimal implementations should just end that line of the response with a CRLF ...
... consists of the message-number of the message, followed by a single space and the exact size of the message in octets. This memo makes no requirement on what follows the message size in the scan listing. Minimal implementations should just end that line of the response with a CRLF ...



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