Document that -T markdown produces ASCII output, and the implied

limitations.  Of course, we could write UTF-8 output instead,
but even the CommonMark specification doesn't require parsers
to support that, so portability would be doubtful.

While here, provide a link to the CommonMark specification.

1 files changed, 10 insertions, 0 deletions

diff --git a/mandoc.1 b/mandoc.1
index ab49f5e8..8cb5a8b1 100644
--- a/mandoc.1
+++ b/mandoc.1
@@ -465,6 +465,16 @@ input to the
 format conforming to
 .Lk http://daringfireball.net/projects/markdown/syntax.text\
  "John Gruber's 2004 specification" .
+The output also almost conforms to the
+.Lk http://commonmark.org/ CommonMark
+specification.
+.Pp
+The character set used for the markdown output is ASCII.
+Non-ASCII characters are encoded as HTML entities.
+Since that is not possible in literal font contexts, because these
+are rendered as code spans and code blocks in the markdown output,
+non-ASCII characters are transliterated to ASCII approximations in
+these contexts.
 .Pp
 Markdown is a very weak markup language, so all semantic markup is
 lost, and even part of the presentational markup may be lost.