Re: [ietf-smtp] Stray <LF> in the middle of messages

Paul Smith <> Wed, 10 June 2020 13:16 UTC

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Subject: Re: [ietf-smtp] Stray <LF> in the middle of messages
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On 10/06/2020 12:33, Keith Moore wrote:
> The CRLF convention for transfer of Internet text files (in FTP, which 
> was the first protocol used to send email on the ARPAnet), predates 
> the existence of both PC-DOS and MacOS by several years.   I am 
> guessing that FTP got its end-of-line convention for text files from 

Strictly speaking, CRLF is the "right" one to use given those control 
codes' definitions.

CR takes you back to the start of the current line, and LF takes you to 
the next line (at the current position), so to get to the start of the 
next line, you need either CRLF or LFCR (AIUI CRLF was chosen to give 
the print head more time to go back to the start of the line).

I remember sending CR (without LF) to a printer, and then reprinting the 
last line to make it print 'bold'.



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