Attachment altered because of 7 bit (none) encoding.
Dear list,
I noticed that some of the .lyx files I sent via mutt were altered (an
extra dot is added) at lines with a leading dot. I did some
research/experiments and find that:
1. .lyx is a pure text file format that tends to have lines with leading dot,
2. without an .mime.types entry, mutt does not encode .lyx file.
3. According to RFC 821, such lines will be added an extra dot
4. Mail clients may or may not remove these extra dots.
After I add 'application/lyx lyx' to my .mime.types, mutt encodes the
attachment and the problem disappears. However, I do think mutt's
behavior is unsafe and pine's treatment of this problem is better:
http://www.washington.edu/pine/faq/attachments.html
7.2 Why does Pine encode text attachments?
Pine uses MIME's Base64 encoding for all attachments, including text,
in order to assure that they are not modified in transit. The goal is
make sure that sending file attachments in Pine is as dependable as
using FTP.
Although it may seem like encoding is unnecessary for files that are
plain text, certain email gateway, trasport, and delivery agents pose
a threat to the integrity of even text files (much less binary files).
For example, long lines may be wrapped, trailing spaces deleted, tabs
turned into spaces, lines beginning with "From" modified, etc.
So my questions are:
1. Is there a way to encode attachment in base64 format by default for
all text files (or all files if that will not cause any trouble.)?
2. Is it a good idea to make this the default behavior of mutt? (Following pine)
I am using mutt 1.4i on a Solaris machine.
Thank you very much.
Bo