[ietf-822] Question about line folding and maximum line length
Bryan Frimin <bryan@frimin.fr> Thu, 06 May 2021 13:52 UTC
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From: Bryan Frimin <bryan@frimin.fr>
To: ietf-822@ietf.org
Date: Thu, 06 May 2021 15:52:08 +0200
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Subject: [ietf-822] Question about line folding and maximum line length
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Hello everyone, I am implementing an e-mail client. I have to implement the SMTP protocol, starting with the internet message format defined by RFC 5322[1]. After reading the RFC, I found two points that are not clear to me. 1. The maximum line length. RFC 5322 section 2.1.1[2] describes two possible line length limits. The historical one, 78 characters, and the new one, 998 characters. Is the historical limit still relevant for an email client in 2021, or can I just use the new one? 2. The long line folding mechanism. RFC 5322 section 2.2.3[3] defines a folding mechanism for long header fields. But it does define whether it is possible to fold a header field name longer than the limit (yes it is an edge case, but it could happen). And folding can only be done if a lexical token or a space is present. So what about values without any separator ? Regards, [1] https://tools.ietf.org/html/rfc5322 [2] https://tools.ietf.org/html/rfc5322#section-2.1.1 [3] https://tools.ietf.org/html/rfc5322#section-2.2.3 -- Bryan Frimin https://www.frimin.fr bryan@frimin.fr
- [ietf-822] Question about line folding and maximu… Bryan Frimin
- Re: [ietf-822] Question about line folding and ma… Paul Smith
- Re: [ietf-822] Question about line folding and ma… John Levine
- Re: [ietf-822] Question about line folding and ma… Pete Resnick
- Re: [ietf-822] Question about line folding and ma… Hector Santos