Setting Up For MIME

Your system administrator has probably set up some reasonable mhn defaults for composing and showing multi-media e-mail messages. These defaults may or may not be adequate for the kinds of multi-media e-mail messages that you receive or compose.

To compose multi-media e-mail messages using pre-existing files requires no special setup; it's displaying them that definitely requires setup.

When you display a message by using show or mhn -show, you might see error messages like this one:

mhn: don't know how to display content
     (content video/mpeg in message /home/jsweet/Mail/drafts/15)

A ``don't know how to display'' error message like the one above means that mhn hasn't been informed how to display a particular type of message part. This problem may or may not be easy to fix, depending on whether you have a program around that can display the particular type of data involved.

Mhn looks in several places for information about how to compose or to display multi-media message parts. Your .mh_profile is one such place.

The .mh_profile file in your home directory exists to permit customizations of the behaviors of MH programs. Many MH users never bother changing the defaults. However, for using mhn, changing the .mh_profile is almost unavoidable. However, it may not be necessary to change your .mh_profile if you're happy with the system defaults.

By using an appropriate display program in an appropriate profile entry, mhn can be informed how to run a program to display a particular type of message part.

For example, mhn can be instructed to use the xv program to display image/gif data on an X Window System display. If you don't have the xv program, it's certainly possible to obtain it and to compile it for yourself; it's freely available via anonymous FTP from a number of Internet sites. However, you may have some other program on your system capable of displaying GIF files, in which case you could use that program instead of xv.

Profile entries can be overridden in message drafts by using appropriate program invocations in the place of file names in the mhn directives.

Information about how to obtain various programs that can display multi-media message parts can be found in appendix [*]. It may also be useful to track down a highly informative document in the MH source tree, miscellany/multimedia/READ-ME.



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