-For contents of type message/external-body,
-.B mhshow
-supports these access-types:
-.PP
-.IP \(bu 4
-afs
-.IP \(bu 4
-anon-ftp
-.IP \(bu 4
-ftp
-.IP \(bu 4
-local-file
-.IP \(bu 4
-mail-server
-.PP
-For the \*(lqanon-ftp\*(rq and \*(lqftp\*(rq access types,
-.B mhshow
-will look for the \*(lqnmh-access-ftp\*(rq
-profile entry, e.g.,
-.PP
-.RS 5
-nmh-access-ftp: myftp.sh
-.RE
-.PP
-to determine the pathname of a program to perform the FTP retrieval.
-.PP
-This program is invoked with these arguments:
-.PP
-.RS 5
-.nf
-domain name of FTP-site
-username
-password
-remote directory
-remote filename
-local filename
-\*(lqascii\*(rq or \*(lqbinary\*(rq
-.fi
-.RE
-.PP
-The program should terminate with an exit status of zero if the
-retrieval is successful, and a non-zero exit status otherwise.
-.PP
-If this entry is not provided, then
-.B mhshow
-will use a simple
-built-in FTP client to perform the retrieval.
-.SS "The Content Cache"
-When
-.B mhshow
-encounters an external content containing a
-\*(lqContent-ID:\*(rq field, and if the content allows caching, then
-depending on the caching behavior of
-.BR mhshow ,
-the content might be read from or written to a cache.
-.PP
-The caching behavior of
-.B mhshow
-is controlled with the
-.B \-rcache
-and
-.B \-wcache
-switches, which define the policy for reading from,
-and writing to, the cache, respectively. One of four policies may be
-specified: \*(lqpublic\*(rq, indicating that
-.B mhshow
-should make use
-of a publically-accessible content cache; \*(lqprivate\*(rq, indicating
-that
-.B mhshow
-should make use of the user's private content cache;
-\*(lqnever\*(rq, indicating that
-.B mhshow
-should never make use of
-caching; and, \*(lqask\*(rq, indicating that
-.B mhshow
-should ask the user.
-.PP
-There are two directories where contents may be cached: the profile entry
-\*(lqnmh-cache\*(rq names a directory containing world-readable contents, and,
-the profile entry \*(lqnmh-private-cache\*(rq names a directory containing
-private contents. The former should be an absolute (rooted) directory
-name.
-.PP
-For example,
-.PP
-.RS 5
-nmh-cache: /tmp
-.RE
-.PP
-might be used if you didn't care that the cache got wiped after each
-reboot of the system. The private cache is interpreted relative to the user's
-mail storage, if not rooted, e.g.,
-.PP
-.RS 5
-nmh-private-cache: .cache
-.RE
-.PP
-(which is the default value).