mailcap - MIME capabilities file, as used by af

The mailcap file lists the known MIME content-types, and describes how to display, print, and compose each content-type.

Lines in the file which start with a '#' are treated as comments and ignored, as are blank lines. Each other line contains a single mailcap entry. Long entries may be continued onto the next line by ending them with a '\'.

Each mailcap entry consists of at least a content-type, and a command to execute to display that content-type. It may be followed by one or more optional fields, which give further information about how to handle the content-type.

The content-type may be any valid MIME content-type, in the form type/subtype. In addition, if no subtype is specified, or a '*' is used as the subtype, then the content-type will match any subtype of the primary type.

The command may be any UNIX command, and is called to display messages of the given content-type. All commands must follow the same rules, including those specfied in optional fields.

Any '\' or ';' characters in a command string must be quoted with a strings:

%s

Is replaced by the name of a temporary file containing the message body.

%t

Is replaced by the content-type of the message, excluding any parameters. %{"param"} Is replaced by the value of the parameter named in param, or a blank string if no such parameter has been specified.

%n

Is replaced by the number of body parts if the message is a multipart message, or '0' otherwise.

%F

If the message is a multipart message, then this is replaced with a space-separated list of values, two for each body part. The values give first the content-type of the body part, and then the name of a temporary file where it has been stored.

The optional fields, which can give more information about a content-type are:

test="command"

Describes a command which should be run successfully (ie. returning 0) before the mailcap entry is used. The most common is "test -n $DISPLAY".

print="command"

Describes the command used to print the content-type.

edit="command"

Describes a command to edit a file containing the body of a message of the given content-type.

compose="command"

composetyped="command"

Describes a command to compose a file containing the body of a message of the given content-type. Any command specified by the composetyped command, must also include a Content-Type: header in the output, which allows the composing command to add parameters to the content-type.

desc="text"

A textual description of the content-type.

file="template"

If any command includes the %s escape, then this field can specify a format for the filename. If %s appears in the template, then it will be replaced with characters to make the name unique.

needsterminal

Indicates that the command is interactive, and needs control of a terminal window to function.

copiousoutput

Indicates that the output of the command should be displayed via a pager.

textualnewlines

Forces af to treat newlines in the message body as it would for text, even though the content-type is not a subtype of text.

x11-bitmap="filename"

Names a file where a bitmap which can be used to mark this content-type is stored. Not used by af.

# A partial mailcap file

# Handle text/enriched and text/richtext text/enriched; richtext -e; copiousoutput; \ description="Enriched text" text/richtext; richtext; copiousoutput; \ description="Richtext"

# Display audio/basic using the audio device audio/basic; cat > /dev/audio; \ description="An audio fragment"

# Handle PostScript files by printing them # (this is a security hole) application/postscript; lpr %s; \ description="A PostScript File"

$HOME/.mailcap user's mailcap file

/etc/af/mailcap

global mailcap file for af.

/etc/mailcap,

/usr/etc/mailcap,

/usr/local/etc/mailcap

global mailcap files for all mailers.

Malc Arnold, based on a specification by Nathaniel Borenstein.

af(1), ``The Af Reference Manual'', rfc1524.