-If defined and set to 1, then the
-.B whatnow
-program will automatically
-invoke the buildmimeproc (discussed below) to process each message as a MIME
-composition draft before it is sent.
-(profile, no default)
+The (pseudo) header in draft messages, that contains files to be attached
+to the message on sending.
+If you like to type a lot, name it `X-MH-Attachment'.
+(profile, default: `Attach')
+.RE
+.PP
+.BR Mime-Type-Query :
+file \-b \-\-mime
+.RS 5
+A command that prints the MIME type of a file.
+The file name gets appended to the command line.
+Note: Older GNU versions of file(1) won't generate the desired
+output. GNU file-4.26, for instance, omits a required semicolon.
+GNU file-5.04 is known to work. Non-GNU version likely need different
+options or don't provide this function at all. Alternatively, you can use
+.BR print\-mimetype ,
+which is part of mmh, but guesses MIME types by file name extensions only.