-If `\-push' is specified, \fIsend\fR will detach itself from the user's
-terminal and perform its actions in the background. If \fIpush\fR\0'd
-and the draft can't be sent, then an error message will be sent (using
-the mailproc) back to the user. If `\-forward' is given, then a copy
-of the draft will be attached to this failure notice. Using `\-push'
-differs from putting \fIsend\fR in the background because the output is
-trapped and analyzed by \fInmh\fR.
+.PP
+By default the draft is scanned for a header named
+.IR Nmh-Attachment .
+The draft is converted to a MIME message if one or more matches are found.
+This conversion occurs before all other processing. The header name
+can be changed with the
+.B \-attach
+option. This behavior can be disabled completely with the
+.B \-noattach
+option. The
+.B whatnow
+man page describes the user interface for managing MIME attachments via
+this mechanism.
+.PP
+The first part of the MIME message is the draft body if that body contains
+any non-blank characters.
+The body of each header field whose name matches the
+.I header-field-name
+is interpreted as a file name, and each file named is included as a separate
+part in the MIME message.
+.PP
+For file names with dot suffixes, the profile is scanned for a
+.I mhshow-suffix-
+entry for that suffix.
+The content-type for the part is taken from that profile entry if a match is
+found. If a match is not found in the user profile, the mhn.defaults
+profile is scanned next.
+If no match is found or the file does not have a dot suffix, the content-type
+is text/plain if the file contains only ASCII characters or application/octet-stream
+if it contains characters outside of the ASCII range. See
+.BR mhshow (1)
+for more details and example syntax.
+.PP
+Each part contains a name attribute that is the last component of the path name.
+A
+.I x-unix-mode
+attribute containing the file mode accompanies each part.
+Finally, a description attribute is generated by running the
+.I file
+command on the file.
+.PP
+The
+.B -attachformat
+option specifies the MIME header field formats: a value of
+.B 0
+includes the
+.I x-unix-mode
+attribute as noted above. A value of
+.BR 1 ,
+the default,
+suppresses that, puts the file name in the
+\*(lqContent-Description\*(rq header, and
+adds a \*(lqContent-Disposition\*(rq header. A value of
+.B 2
+adds the file
+.I modification-date
+parameter to the \*(lqContent-Disposition\*(rq header. You can
+specify one value in your profile, and override it for individual
+messages at the
+.I whatnow
+prompt.
+.PP
+Here are example message part headers, for an attachment, for each of the
+.B -attachformat
+values:
+.PP
+.nf
+-attachformat 0:
+Content-Type: text/plain; name="VERSION"; x-unix-mode="0644";
+ charset="us-ascii"
+Content-Description: ASCII text