RFC 5322 discusses line lengths both in terms of the maximum line length an MTA
can be required to handle (998 bytes) but also a more conservative 78 character
limit, driven by the requirement to support user interfaces that are only 78
If I'm wrapping a header by breaking a line with "\r\n\t", and I'm trying to
comply with the spirit of the RFC, how many characters am I allowed to put on
the continuation line?
Is it 77, as I have a single tab character already, and I'm allowed 78 total?
Or is it 72, as in the glass teletype world the RFC seems to live in the tab
character will consume 8 display characters to the first tab stop, leaving me
another 72 before I run into the right edge of the screen?
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