mirror of
https://github.com/rkd77/elinks.git
synced 2024-12-04 14:46:47 -05:00
130 lines
4.9 KiB
Plaintext
130 lines
4.9 KiB
Plaintext
Managing External Viewers with Mailcap
|
|
--------------------------------------
|
|
|
|
This document describes the support for Mailcap (RFC 1524) in ELinks. It does
|
|
not describe the mailcap format. There are plenty of documents on the Web that
|
|
does this. Google and thou wilt find. ;)
|
|
|
|
|
|
A Short Intro to Mailcap
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Mailcap is a file format defined in RFC 1524. Its purpose is to inform
|
|
multiple mail reading user agent (MUA) programs about the locally-installed
|
|
facilities for handling mail in various formats. It is designed to work with
|
|
the Multipurpose Internet Mail Extensions, known as MIME.
|
|
|
|
ELinks allows MIME handlers to be defined using its own configuration system,
|
|
so why support mailcap? It can be seen as an alternative or simply as a
|
|
supplement for setting up MIME handlers in ELinks. Mailcap files are present
|
|
on most UNIX systems--usually in /etc/mailcap--so this makes it possible for
|
|
ELinks to know how to handle a great variety of file formats with little
|
|
configuration. To be able to use mailcap, it has to be compiled into ELinks.
|
|
This is the default. If you don't need mailcap support, just configure ELinks
|
|
with the flag: --disable-mailcap.
|
|
|
|
|
|
Parameters to Mailcap Entries
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
The code has been ported from Mutt and thereby inherits some of its various
|
|
features and limitation.
|
|
|
|
The following parameters are supported:
|
|
|
|
`---------------`-------------------------------------------------------------
|
|
Parameter Description
|
|
------------------------------------------------------------------------------
|
|
%s The filename that contains the data.
|
|
%f The content type, like 'text/plain'.
|
|
------------------------------------------------------------------------------
|
|
|
|
The following parameters are not supported, since they do not really make much
|
|
sense for a non-MUA program:
|
|
|
|
`---------------`-------------------------------------------------------------
|
|
Parameter Description
|
|
------------------------------------------------------------------------------
|
|
%n The integer number of sub-parts in the multipart
|
|
%F The "content-type filename" repeated for each sub-part
|
|
%{ parameter} The "parameter" value from the content-type field
|
|
------------------------------------------------------------------------------
|
|
|
|
|
|
Reading of Mailcap Files
|
|
~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Mailcap files will be read when starting ELinks. The mailcap files to use will
|
|
be found from the mailcap path, a colon separated list of files similar to the
|
|
$PATH environment variable. The mailcap path will be determined in the
|
|
following way:
|
|
|
|
- From the value of the mime.mailcap.path option in elinks.conf; for example:
|
|
|
|
set mime.mailcap.path = "~/.mailcap:/usr/local/etc/mailcap"
|
|
|
|
- From MAILCAP environment variable.
|
|
|
|
- If non of the above is defined, the mailcap path defaults to
|
|
`~/.mailcap:/etc/mailcap`.
|
|
|
|
|
|
Fields
|
|
~~~~~~
|
|
|
|
Since mailcap handling is primarily for displaying of resources, all fields
|
|
like edit, print, compose etc. are ignored.
|
|
|
|
Note: Test commands are supported, but unfortunately, it's not possible to
|
|
provide the file when running the test. So any test that requires a file will
|
|
be considered failed and the handler will not be used.
|
|
|
|
Unfortunately, there are no 'native' support for the copiousoutput field. The
|
|
field basically mean 'needs pager'. So it is handled by appending a pipe and a
|
|
pager program to the command. The pager program will be read from the `PAGER`
|
|
environment variable. If this fails, test are made for common pager programs
|
|
(`/usr/bin/pager`, `/usr/bin/less` and `/usr/bin/more` in that order). So if you
|
|
define png2ascii as your handler for image/png and specify copiousoutput then
|
|
the executed command will be "`png2ascii |/usr/bin/less`" if less is your pager
|
|
or present on your system.
|
|
|
|
|
|
Mailcap Configuration
|
|
~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Apart from the mime.mailcap.path option, you can configure if mailca support
|
|
should be disabled. The default being that it is enabled. To disable it just
|
|
put:
|
|
|
|
set mime.mailcap.enable = 0
|
|
|
|
in elinks.conf.
|
|
|
|
It is also possible to control wether ELinks should ask you before opening a
|
|
file. The option is a boolian and can be set like this:
|
|
|
|
set mime.mailcap.ask = 1
|
|
|
|
if you would like to be asked before opening a file.
|
|
|
|
|
|
Some Sample Mailcap Entries
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
Below are examples of how to specify external viewers:
|
|
|
|
-------------------------------------------------------------------------------
|
|
# Use xv if X is running
|
|
image/*; xv %s ; test=test -n "$DISPLAY";
|
|
|
|
text/x-csrc; view %s; needsterminal
|
|
|
|
# Various multimedia files
|
|
audio/mpeg; xmms '%s'; test=test -n "$DISPLAY";
|
|
application/pdf; xpdf '%s'; test=test -n "$DISPLAY";
|
|
application/postscript; ps2ascii %s ; copiousoutput
|
|
-------------------------------------------------------------------------------
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
///////////////////////////////////////////////////////////////////////////////
|