On Fri, Mar 10, 2017 at 9:21 PM, Mary Ann Horton <mah@mhorton.net> wrote:

So you'd think, but it appears it came first in netnews. Mail/mailx has ~m which indents with a tab, not a ">". Most likely in summer of 1983, between 2.10 and 2.10.1.

Wasn't it possible to customize this in .mailrc? Something like, `set indentprefix="> "`? I'm afraid that doesn't answer the question, but I'm not sure mailx/Mail as the vector is unreasonable. Is it possible someone coming from the ARPAnet mailing list world found Unix and brought the practice in? I'm curious what the standard was on ITS or TOPS-20, for instance.

- Dan C.