NAME
update-mime - create or update MIME information
SYNOPSIS
update-mime [no parameters]
DESCRIPTION
update-mime updates the /etc/mailcap file to reflect mime information
changed by a Debian package during installation or removal.
OVERRIDING ORDER
The order of entries in the /etc/mailcap file can be altered by editing
the /etc/mailcap.order file. Please see the mailcap.order(5) man page
for more information.
CREATING ENTRIES
To create entries in the mailcap file, packages need to create a file
in the /usr/lib/mime/packages directory. In this file goes the
verbatim desired mailcap entries. In addition to the standard mailcap
options (described below) is a new priority option. Specifying this
will provide for simple ranking of programs within a given mime type.
An animation viewer, for example, may be able to display a static
picture, but probably wouldn’t be the best choice and so would give an
option like "priority=2". Priorities range from 0 to 9, with 0 being
the lowest and 9 being the highest. If the priority option is omitted,
a value of 5 is used.
The following are standard options that can be specified in the mailcap
entry. Options are separated by semicolons (;) but must all be on the
same line. Each line should look like:
mime/type; viewer; option; another=val; etc; priority=5
Mime types of the form "class/*" and even "*/*" are now acceptable
(they were previously disallowed). When using "class/*", it is
probably a good idea to add a "priority=[1-4]" option so specific rules
using the default priority will get chosen first. If using "*/*",
though, you probably want to add a "priority=0" option to make that
rule a "last resort".
Commands
<program-string>
Specifies the program to run to view a file of the given
content-type. This option setting connot be omitted. An
implicit "view=" can be considered before it. When writing an
entry that has no viewer, use a value of false in this space.
compose=<program-string>
The "compose" command may be used to specify a program that can
be used to compose a new body or body part in the given format.
Its intended use is to support mail composing agents that
support the composition of multiple types of mail using external
composing agents. The result of the composing program may be
data that is not yet suitable for mail transport -- that is, a
Content-Transfer-Encoding may need to be applied to the data.
composetyped=<program-string>
The "composetyped" command is similar to "compose", but is to be
used when the composing program needs to specify the Content-
type header field to be applied to the composed data. The
"compose" option is simpler, and is preferred for use with
existing (non-mail-oriented) programs for composing data in a
given format. The "composetyped" option is necessary when the
Content-type information must include auxiliary parameters, and
the composition program must then know enough about mail formats
to produce output that includes the mail type information.
edit=<program-string>
The "edit" command may be used to specify a program that can be
used to edit a body or body part in the given format. In many
cases, it may be identical in content to the "compose" command.
print=<program-string>
The "print" command may be used to specify a program that can be
used to print a message or body part in the given format.
Modifiers
These options are modifiers to all the commands specified on the
command line.
test=<conditional>
The "test" option may be used to test some external condition
(e.g., the machine architecture, or the window system in use) to
determine whether or not the mailcap line applies. It specifies
a program to be run to test some condition. If the test fails,
a subsequent mailcap entry will be sought. Multiple test
options are not permitted -- since a test can call a program, it
can already be arbitrarily complex.
Note: When testing for X by looking at the DISPLAY environment
variable, please use one of:
test=test -z "$DISPLAY" (no X)
or test=test -n "$DISPLAY" (have X)
Many programs recognize these strings and optimize for them.
needsterminal
The "needsterminal" option, if given, indicates that the
commands must be run on an interactive terminal. This is needed
to inform window-oriented user agents that an interactive
terminal is needed. (The decision is not left exclusively to
the command because in some circumstances it may not be possible
for such programs to tell whether or not they are on interactive
terminals.) The needsterminal command applies to the view,
compose and edit commands, if they exist. Note that this is NOT
a test -- it is a requirement for the environment in which the
program will be executed, and will typically cause the creation
of a terminal window when not executed on either a real terminal
or a terminal window.
copiousoutput
The "copiousoutput" option, if given, indicates that the output
from the view-command will be an extended stream of output and
is to be interpreted as advice to the UA (User Agent mail-
reading program) that the output should be either paged or made
scrollable. Note that it is probably a mistake if needsterminal
and copiousoutput are both specified.
Content-Type Info
These options provide additional information about the given content-
type.
description=<string>
The "description" option simply provides a textual description
that describes the type of data, to be used optionally by mail
readers that wish to describe the data before offering to
display it.
textualnewlines
The "textualnewlines" option, if given, indicates that this type
of data is line-oriented and that, if encoded in a binary
format, all newlines should be converted to canonical form
(CRLF) before encoding, and will be in that form after decoding.
In general, this is needed only if there is line-oriented data
of some type other than text/* or non-line-oriented data that is
a subtype of text.
x11-bitmap=<pathname>
The "x11-bitmap" option names a file, in X11 bitmap (xbm)
format, which points to an appropriate icon to be used to
visually denote the presence of this kind of data.
nametemplate=<string>
The "nametemplate" option gives a file name format, in which %s
will be replaced by a short unique string to give the name of
the temporary file to be passed to the viewing command. This is
only expected to be relevant in environments where filename
extensions are meaningful, e.g., one could specify that a GIF
file being passed to a gif viewer should have a name ending in
".gif" by using "nametemplate=%s.gif".
DEPENDENCIES
Packages that wish to provide MIME access to themselves should not
depend on, recommend, or suggest mime-support. Instead, they should
just put something like the following in the postinst and postrm
scripts.
if [ -x /usr/sbin/update-mime ]; then
update-mime
fi
SEE ALSO
mailcap.order(5), RFC-2046, RFC-1524
AUTHOR
update-mime was written by Brian White <bcwhite@pobox.com>
COPYRIGHT
update-mime is in the public domain (the only true "free").