fix index weirdness if mailbox is emptied while inside the pager (Closes: 375530)

[software/mutt-debian.git] / doc / muttrc.man.head

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.TH muttrc 5 "September 2002" Unix "User Manuals"
.SH NAME
muttrc \- Configuration file for the Mutt Mail User Agent
.SH DESCRIPTION
.PP
A mutt configuration file consists of a series of \(lqcommands\(rq.
Each line of the file may contain one or more commands.  When
multiple commands are used, they must be separated by a semicolon
(\(lq\fB;\fP\(rq).
.PP
The hash mark, or pound sign (\(lq\fB#\fP\(rq), is used as a
\(lqcomment\(rq character. You can use it to annotate your
initialization file. All text after the comment character to the end
of the line is ignored.
.PP
Single quotes (\(lq\fB'\fP\(rq) and double quotes (\(lq\fB"\fP\(rq)
can be used to quote strings which contain spaces or other special
characters.  The difference between the two types of quotes is
similar to that of many popular shell programs, namely that a single
quote is used to specify a literal string (one that is not
interpreted for shell variables or quoting with a backslash [see
next paragraph]), while double quotes indicate a string which
should be evaluated.  For example, backticks are evaluated inside of
double quotes, but not single quotes.
.PP
\fB\(rs\fP quotes the next character, just as in shells such as bash and zsh.
For example, if want to put quotes (\(lq\fB"\fP\(rq) inside of a
string, you can use \(lq\fB\(rs\fP\(rq to force the next character
to be a literal instead of interpreted character.
.PP
\(lq\fB\(rs\(rs\fP\(rq means to insert a literal \(lq\fB\(rs\fP\(rq into the
line.  \(lq\fB\(rsn\fP\(rq and \(lq\fB\(rsr\fP\(rq have their usual
C meanings of linefeed and carriage-return, respectively.
.PP
A \(lq\fB\(rs\fP\(rq at the end of a line can be used to split commands over
multiple lines, provided that the split points don't appear in the
middle of command names.
.PP
It is also possible to substitute the output of a Unix command in an
initialization file.  This is accomplished by enclosing the command
in backticks (\fB`\fP\fIcommand\fP\fB`\fP).
.PP
UNIX environment variables can be accessed like the way it is done in shells
like sh and bash: Prepend the name of the variable by a dollar
(\(lq\fB\(Do\fP\(rq) sign.
.PP
.SH COMMANDS
.PP
.nf
\fBalias\fP [\fB-group\fP \fIname\fP [...]] \fIkey\fP \fIaddress\fP [\fB,\fP \fIaddress\fP [ ... ]]
\fBunalias\fP [\fB * \fP | \fIkey\fP ]
.fi
.IP
\fBalias\fP defines an alias \fIkey\fP for the given addresses. Each
\fIaddress\fP will be resolved into either an email address (user@example.com)
or a named email address (User Name <user@example.com>). The address may be specified in either format, or in the format \(lquser@example.com (User
Name)\(rq.
\fBunalias\fP removes the alias corresponding to the given \fIkey\fP or
all aliases when \(lq\fB*\fP\(rq is used as an argument. The optional
\fB-group\fP argument to \fBalias\fP causes the aliased address(es) to be
added to the named \fIgroup\fP.
.PP
.nf
\fBgroup\fP [\fB-group\fP \fIname\fP] [\fB-rx\fP \fIEXPR\fP [ \fI...\fP ]] [\fB-addr\fP \fIaddress\fP [ \fI...\fP ]]
\fBungroup\fP [\fB-group\fP \fIname\fP ] [ \fB*\fP | [[\fB-rx\fP \fIEXPR\fP [ \fI...\fP ]] [\fB-addr\fP \fIaddress\fP [ \fI...\fP ]]]
.fi
.IP
\fBgroup\fP is used to directly add either addresses or regular expressions to
the specified group or groups. The different categories of arguments to the
\fBgroup\fP command can be in any order. The flags \fI-rx\fP and \fI-addr\fP
specify what the following strings (that cannot begin with a hyphen) should be
interpreted as: either a regular expression or an email address, respectively.
\fBungroup\fP is used to remove addresses or regular expressions from the
specified group or groups. The syntax is similar to the \fBgroup\fP command,
however the special character \fB*\fP can be used to empty a group of all of
its contents.
.IP
These address groups can also be created implicitly by the \fBalias\fP, \fBlists\fP,
\fBsubscribe\fP and \fBalternates\fP commands by specifying the optional \fI-group\fP
option.
.IP
Once defined, these address groups can be used in patterns to search for and limit the
display to messages matching a group.
.PP
.nf
\fBalternates\fP [\fB-group\fP \fIname\fP] \fIregexp\fP [ \fB,\fP \fIregexp\fP [ ... ]]
\fBunalternates\fP [\fB * \fP | \fIregexp\fP [ \fB,\fP \fIregexp\fP [ ... ]] ]
.fi
.IP
\fBalternates\fP is used to inform mutt about alternate addresses
where you receive mail; you can use regular expressions to specify
alternate addresses.  This affects mutt's idea about messages
from you, and messages addressed to you.  \fBunalternates\fP removes
a regular expression from the list of known alternates. The \fB-group\fP flag
causes all of the subsequent regular expressions to be added to the named group.
.PP
.nf
\fBalternative_order\fP \fItype\fP[\fB/\fP\fIsubtype\fP] [ ... ]
\fBunalternative_order\fP [\fB * \fP | \fItype\fP/\fIsubtype\fP] [...]
.fi
.IP
\fBalternative_order\fP command permits you to define an order of preference which is
used by mutt to determine which part of a
\fBmultipart/alternative\fP body to display.
A subtype of \(lq\fB*\fP\(rq matches any subtype, as does an empty
subtype.   \fBunalternative_order\fP removes entries from the
ordered list or deletes the entire list when \(lq\fB*\fP\(rq is used
as an argument.
.PP
.nf
\fBauto_view\fP \fItype\fP[\fB/\fP\fIsubtype\fP] [ ... ]
\fBunauto_view\fP \fItype\fP[\fB/\fP\fIsubtype\fP] [ ... ]
.fi
.IP
This commands permits you to specify that mutt should automatically
convert the given MIME types to text/plain when displaying messages.
For this to work, there must be a 
.BR mailcap (5)
entry for the given MIME type with the 
.B copiousoutput
flag set.  A subtype of \(lq\fB*\fP\(rq 
matches any subtype, as does an empty subtype.
.PP
.nf
\fBmime_lookup\fP \fItype\fP[\fB/\fP\fIsubtype\fP] [ ... ]
\fBunmime_lookup\fP \fItype\fP[\fB/\fP\fIsubtype\fP] [ ... ]
.fi
.IP
This command permits you to define a list of "data" MIME content
types for which mutt will try to determine the actual file type from
the file name, and not use a 
.BR mailcap (5)
entry given for the original MIME type.  For instance, you may add
the \fBapplication/octet-stream\fP MIME type to this list.
.TP
\fBbind\fP \fImap1,map2,...\fP \fIkey\fP \fIfunction\fP
This command binds the given \fIkey\fP for the given \fImap\fP or maps
to the given \fIfunction\fP. Multiple maps may be specified by
separating them with commas (no whitespace is allowed).
.IP
Valid maps are:
.BR generic ", " alias ", " attach ", " 
.BR browser ", " editor ", "
.BR index ", " compose ", " 
.BR pager ", " pgp ", " postpone ", "
.BR mix .
.IP
For more information on keys and functions, please consult the Mutt
Manual.
.TP
\fBaccount-hook\fP [\fB!\fP]\fIregexp\fP \fIcommand\fP
This hook is executed whenever you access a remote mailbox. Useful
to adjust configuration settings to different IMAP or POP servers.
.TP
\fBcharset-hook\fP \fIalias\fP \fIcharset\fP
This command defines an alias for a character set.  This is useful
to properly display messages which are tagged with a character set
name not known to mutt.
.TP
\fBiconv-hook\fP \fIcharset\fP \fIlocal-charset\fP
This command defines a system-specific name for a character set.
This is useful when your system's 
.BR iconv (3)
implementation does not understand MIME character set names (such as 
.BR iso-8859-1 ),
but instead insists on being fed with implementation-specific
character set names (such as
.BR 8859-1 ).
In this specific case, you'd put this into your configuration file:
.IP
.B "iconv-hook iso-8859-1 8859-1"
.TP
\fBmessage-hook\fP [\fB!\fP]\fIpattern\fP \fIcommand\fP
Before mutt displays (or formats for replying or forwarding) a
message which matches the given \fIpattern\fP (or, when it is
preceded by an exclamation mark, does not match the \fIpattern\fP),
the given \fIcommand\fP is executed.  When multiple
\fBmessage-hook\fPs match, they are  executed  in  the order in
which they occur in the configuration file.
.TP
\fBfolder-hook\fP [\fB!\fP]\fIregexp\fP \fIcommand\fP
When mutt enters a folder which matches \fIregexp\fP (or, when
\fIregexp\fP is preceded by an exclamation mark, does not match
\fIregexp\fP), the given \fIcommand\fP is executed.
.IP
When several \fBfolder-hook\fPs match a given mail folder, they are
executed in the order given in the configuration file.
.TP
\fBmacro\fP \fImap\fP \fIkey\fP \fIsequence\fP [ \fIdescription\fP ]
This command binds the given \fIsequence\fP of keys to the given
\fIkey\fP in the given \fImap\fP or maps.  For valid maps, see \fBbind\fP. To
specify multiple maps, put only a comma between the maps.
.PP
.nf
\fBcolor\fP \fIobject\fP \fIforeground\fP \fIbackground\fP [ \fI regexp\fP ]
\fBcolor\fP index \fIforeground\fP \fIbackground\fP [ \fI pattern\fP ]
\fBuncolor\fP index \fIpattern\fP [ \fIpattern\fP ... ]
.fi
.IP
If your terminal supports color, these commands can be used to
assign \fIforeground\fP/\fIbackground\fP combinations to certain
objects.  Valid objects are:
.BR attachment ", " body ", " bold ", " header ", "
.BR hdrdefault ", " index ", " indicator ", " markers ", "
.BR message ", " normal ", " quoted ", " quoted\fIN\fP ", "
.BR search ", " signature ", " status ", " tilde ", " tree ", "
.BR underline .
The
.BR body " and " header
objects allow you to restrict the colorization to a regular
expression.  The \fBindex\fP object permits you to select colored
messages by pattern.
.IP
Valid colors include:
.BR white ", " black ", " green ", " magenta ", " blue ", "
.BR cyan ", " yellow ", " red ", " default ", " color\fIN\fP .
.PP
.nf
\fBmono\fP \fIobject\fP \fIattribute\fP [ \fIregexp\fP ]
\fBmono\fP index \fIattribute\fP [ \fIpattern\fP ]
.fi
.IP
For terminals which don't support color, you can still assign
attributes to objects.  Valid attributes include:
.BR none ", " bold ", " underline ", " 
.BR reverse ", and " standout .
.TP
[\fBun\fP]\fBignore\fP \fIpattern\fP [ \fIpattern\fP ... ]
The \fBignore\fP command permits you to specify header fields which
you usually don't wish to see.  Any header field whose tag
\fIbegins\fP with an \(lqignored\(rq pattern will be ignored.
.IP
The \fBunignore\fP command permits you to define exceptions from
the above mentioned list of ignored headers.
.PP
.nf
\fBlists\fP [\fB-group\fP \fIname\fP] \fIregexp\fP [ \fIregexp\fP ... ]
\fBunlists\fP \fIregexp\fP [ \fIregexp\fP ... ]
\fBsubscribe\fP [\fB-group\fP \fIname\fP] \fIregexp\fP [ \fIregexp\fP ... ]
\fBunsubscribe\fP \fIregexp\fP [ \fIregexp\fP ... ]
.fi
.IP
Mutt maintains two lists of mailing list address patterns, a list of
subscribed mailing lists, and a list of known mailing lists.  All
subscribed mailing lists are known.  Patterns use regular expressions.
.IP
The \fBlists\fP command adds a mailing list address to the list of
known mailing lists.  The \fBunlists\fP command removes a mailing
list from the lists of known and subscribed mailing lists.  The
\fBsubscribe\fP command adds a mailing list to the lists of known
and subscribed mailing lists.  The \fBunsubscribe\fP command removes
it from the list of subscribed mailing lists. The \fb-group\fP flag
adds all of the subsequent regular expressions to the named group.
.TP
\fBmbox-hook\fP [\fB!\fP]\fIpattern\fP \fImailbox\fP
When mutt changes to a mail folder which matches \fIpattern\fP,
\fImailbox\fP will be used as the \(lqmbox\(rq folder, i.e., read
messages will be moved to that folder when the mail folder is left.
.IP
The first matching \fBmbox-hook\fP applies.
.PP
.nf
\fBmailboxes\fP \fIfilename\fP [ \fIfilename\fP ... ]
\fBunmailboxes\fP [ \fB*\fP | \fIfilename\fP ... ]
.fi
.IP
The \fBmailboxes\fP specifies folders which can receive mail and which will
be checked for new messages.  When changing folders, pressing space
will cycle through folders with new mail.  The \fBunmailboxes\fP
command is used to remove a file name from the list of folders which
can receive mail.  If "\fB*\fP" is specified as the file name, the
list is emptied.
.PP
.nf
\fBmy_hdr\fP \fIstring\fP
\fBunmy_hdr\fP \fIfield\fP
.fi
.IP
Using \fBmy_hdr\fP, you can define headers which will be added to
the messages you compose.  \fBunmy_hdr\fP will remove the given
user-defined headers.
.TP
\fBhdr_order\fP \fIheader1\fP \fIheader2\fP [ ... ]
With this command, you can specify an order in which mutt will
attempt to present headers to you when viewing messages.
.TP
\fBsave-hook\fP [\fB!\fP]\fIpattern\fP \fIfilename\fP
When a message matches \fIpattern\fP, the default file name when
saving it will be the given \fIfilename\fP.
.TP
\fBfcc-hook\fP [\fB!\fP]\fIpattern\fP \fIfilename\fP
When an outgoing message matches \fIpattern\fP, the default file
name for storing a copy (fcc) will be the given \fIfilename\fP.
.TP
\fBfcc-save-hook\fP [\fB!\fP]\fIpattern\fP \fIfilename\fP
This command is an abbreviation for identical \fBfcc-hook\fP and
\fBsave-hook\fP commands.
.TP
\fBsend-hook\fP [\fB!\fP]\fIpattern\fP \fIcommand\fP
When composing a message matching \fIpattern\fP, \fIcommand\fP is
executed.  When multiple \fBsend-hook\fPs match, they are executed
in the order in which they occur in the configuration file.
.TP
\fBsend2-hook\fP [\fB!\fP]\fIpattern\fP \fIcommand\fP
Whenever a message matching \fIpattern\fP is changed (either by
editing it or by using the compose menu), \fIcommand\fP
is executed. When multiple \fBsend2-hook\fPs match, they are
executed in the order in which they occur in the configuration file.
Possible applications include setting the $sendmail variable when a
message's from header is changed.
.IP
\fBsend2-hook\fP execution is not triggered by use of
\fBenter-command\fP from the compose menu.
.TP
\fBreply-hook\fP [\fB!\fP]\fIpattern\fP \fIcommand\fP
When replying to a message matching \fIpattern\fP, \fIcommand\fP is
executed.  When multiple \fBreply-hook\fPs match, they are executed
in the order in which they occur in the configuration file, but all
\fBreply-hook\fPs are matched and executed before \fBsend-hook\fPs,
regardless of their order in the configuration file.
.TP
\fBcrypt-hook\fP \fIpattern\fP \fIkey-id\fP
The crypt-hook command provides a method by which you can
specify the ID of the public key to be used when encrypting messages
to a certain recipient.  The meaning of "key ID" is to be taken
broadly: This can be a different e-mail address, a numerical key ID,
or even just an arbitrary search string.
.TP
\fBpush\fP \fIstring\fP
This command adds the named \fIstring\fP to the keyboard buffer.
.PP
.nf
\fBset\fP [\fBno\fP|\fBinv\fP|\fB&\fP|\fB?\fP]\fIvariable\fP[=\fIvalue\fP] [ ... ]
\fBtoggle\fP \fIvariable\fP [ ... ]
\fBunset\fP \fIvariable\fP [ ... ]
\fBreset\fP \fIvariable\fP [ ... ]
.fi
.IP
These commands are used to set and manipulate configuration
variables.
.IP
Mutt knows four basic types of variables: boolean, number, string
and quadoption.  Boolean variables can be \fBset\fP (true),
\fBunset\fP (false), or \fBtoggle\fPd. Number variables can be assigned
a positive integer value.
.IP
String variables consist of any number of printable characters.
Strings must be enclosed in quotes if they contain spaces or tabs.
You may also use the \(lqC\(rq escape sequences \fB\\n\fP and
\fB\\t\fP for newline and tab, respectively.
.IP
Quadoption variables are used to control whether or not to be
prompted for certain actions, or to specify a default action.  A
value of \fByes\fP will cause the action to be carried out automatically
as if you had answered yes to the question.  Similarly, a value of
\fBno\fP will cause the the action to be carried out as if you had
answered \(lqno.\(rq A value of \fBask-yes\fP will cause a prompt
with a default answer of \(lqyes\(rq and \fBask-no\fP will provide a
default answer of \(lqno.\(rq
.IP
The \fBreset\fP command resets all given variables to the compile
time defaults.  If you reset the special variable \fBall\fP, all
variables will reset to their compile time defaults.
.TP
\fBsource\fP \fIfilename\fP
The given file will be evaluated as a configuration file.
.TP
.nf
\fBspam\fP \fIpattern\fP \fIformat\fP
\fBnospam\fP \fIpattern\fP
.fi
These commands define spam-detection patterns from external spam
filters, so that mutt can sort, limit, and search on
``spam tags'' or ``spam attributes'', or display them
in the index. See the Mutt manual for details.
.TP
\fBunhook\fP [\fB * \fP | \fIhook-type\fP ]
This command will remove all hooks of a given type, or all hooks
when \(lq\fB*\fP\(rq is used as an argument.  \fIhook-type\fP
can be any of the \fB-hook\fP commands documented above.
.SH PATTERNS
.PP
In various places with mutt, including some of the abovementioned
\fBhook\fP commands, you can specify patterns to match messages.
.SS Constructing Patterns
.PP
A simple pattern consists of an operator of the form
\(lq\fB~\fP\fIcharacter\fP\(rq, possibly followed by a parameter
against which mutt is supposed to match the object specified by
this operator.  For some \fIcharacter\fPs, the \fB~\fP may be
replaced by another character to alter the behavior of the match.
These are described in the list of operators, below.
.PP
With some of these operators, the object to be matched consists of
several e-mail addresses.  In these cases, the object is matched if
at least one of these e-mail addresses matches. You can prepend a
hat (\(lq\fB^\fP\(rq) character to such a pattern to indicate that
\fIall\fP addresses must match in order to match the object.
.PP
You can construct complex patterns by combining simple patterns with
logical operators.  Logical AND is specified by simply concatenating
two simple patterns, for instance \(lq~C mutt-dev ~s bug\(rq.
Logical OR is specified by inserting a vertical bar (\(lq\fB|\fP\(rq)
between two patterns, for instance \(lq~C mutt-dev | ~s bug\(rq.
Additionally, you can negate a pattern by prepending a bang
(\(lq\fB!\fP\(rq) character.  For logical grouping, use braces
(\(lq()\(rq). Example: \(lq!(~t mutt|~c mutt) ~f elkins\(rq.
.SS Simple Patterns
.PP
Mutt understands the following simple patterns:
.P
.PD 0
.TP 12
~A
all messages
.TP
~b \fIEXPR\fP
messages which contain \fIEXPR\fP in the message body.
.TP
=b \fISTRING\fP
messages which contain \fISTRING\fP in the message body. If IMAP is enabled, searches for \fISTRING\fP on the server, rather than downloading each message and searching it locally.
.TP
~B \fIEXPR\fP
messages which contain \fIEXPR\fP in the whole message.
.TP
~c \fIEXPR\fP
messages carbon-copied to \fIEXPR\fP
.TP
%c \fIGROUP\fP
messages carbon-copied to any member of \fIGROUP\fP
.TP
~C \fIEXPR\fP
messages either to: or cc: \fIEXPR\fP
.TP
%C \fIGROUP\fP
messages either to: or cc: to any member of \fIGROUP\fP
.TP
~d \fIMIN\fP-\fIMAX\fP
messages with \(lqdate-sent\(rq in a Date range
.TP
~D
deleted messages
.TP
~e \fIEXPR\fP
messages which contain \fIEXPR\fP in the \(lqSender\(rq field
.TP
%e \fIGROUP\fP
messages which contain a member of \fIGROUP\fP in the \(lqSender\(rq field
.TP
~E
expired messages
.TP
~f \fIEXPR\fP
messages originating from \fIEXPR\fP
.TP
%f \fIGROUP\fP
messages originating form any member of \fIGROUP\fP
.TP
~F
flagged messages
.TP
~g
PGP signed messages
.TP
~G
PGP encrypted messages
.TP
~h \fIEXPR\fP
messages which contain \fIEXPR\fP in the message header
.TP
~H \fIEXPR\fP
messages with spam tags matching \fIEXPR\fP
.TP
~i \fIEXPR\fP
messages which match \fIEXPR\fP in the \(lqMessage-ID\(rq field
.TP
~k
messages containing PGP key material
.TP
~l
messages addressed to a known mailing list (defined by either \fBsubscribe\fP or \fBlist\fP)
.TP
~L \fIEXPR\fP
messages either originated or received by \fIEXPR\fP
.TP
%L \fIGROUP\fP
messages either originated or received by any member of \fIGROUP\fP
.TP
~m \fIMIN\fP-\fIMAX\fP
message in the range \fIMIN\fP to \fIMAX\fP
.TP
~n \fIMIN\fP-\fIMAX\fP
messages with a score in the range \fIMIN\fP to \fIMAX\fP
.TP
~N
new messages
.TP
~O
old messages
.TP
~p
messages addressed to you (as defined by \fBalternates\fP)
.TP
~P
messages from you (as defined by \fBalternates\fP)
.TP
~Q
messages which have been replied to
.TP
~r \fIMIN\fP-\fIMAX\fP
messages with \(lqdate-received\(rq in a Date range
.TP
~R
read messages
.TP
~s \fIEXPR\fP
messages having \fIEXPR\fP in the \(lqSubject\(rq field.
.TP
~S
superseded messages
.TP
~t \fIEXPR\fP
messages addressed to \fIEXPR\fP
.TP
~T
tagged messages
.TP
~u
messages addressed to a subscribed mailing list (defined by \fBsubscribe\fP commands)
.TP
~U
unread messages
.TP
~v
message is part of a collapsed thread.
.TP
~V
cryptographically verified messages
.TP
~x \fIEXPR\fP
messages which contain \fIEXPR\fP in the \(lqReferences\(rq field
.TP
~X \fIMIN\fP-\fIMAX\fP
messages with MIN - MAX attachments
.TP
~y \fIEXPR\fP
messages which contain \fIEXPR\fP in the \(lqX-Label\(rq field
.TP
~z \fIMIN\fP-\fIMAX\fP
messages with a size in the range \fIMIN\fP to \fIMAX\fP
.TP
~=
duplicated messages (see $duplicate_threads)
.TP
~$
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.PD 1
.DT
.PP
In the above, \fIEXPR\fP is a regular expression.
.PP
With the \fB~m\fP, \fB~n\fP, \fB~X\fP, and \fB~z\fP operators, you can also
specify ranges in the forms \fB<\fP\fIMAX\fP, \fB>\fP\fIMIN\fP,
\fIMIN\fP\fB-\fP, and \fB-\fP\fIMAX\fP.
.SS Matching dates
.PP
The \fB~d\fP and \fB~r\fP operators are used to match date ranges,
which are interpreted to be given in your local time zone.
.PP
A date is of the form
\fIDD\fP[\fB/\fP\fIMM\fP[\fB/\fP[\fIcc\fP]\fIYY\fP]], that is, a
two-digit date, optionally followed by a two-digit month, optionally
followed by a year specifications.  Omitted fields default to the
current month and year.
.PP
Mutt understands either two or four digit year specifications.  When
given a two-digit year, mutt will interpret values less than 70 as
lying in the 21st century (i.e., \(lq38\(rq means 2038 and not 1938,
and \(lq00\(rq is interpreted as 2000), and values
greater than or equal to 70 as lying in the 20th century.
.PP
Note that this behaviour \fIis\fP Y2K compliant, but that mutt
\fIdoes\fP have a Y2.07K problem.
.PP
If a date range consists of a single date, the operator in question
will match that precise date.  If the date range consists of a dash
(\(lq\fB-\fP\(rq), followed by a date, this range will match any
date before and up to the date given.  Similarly, a date followed by
a dash matches the date given and any later point of time.  Two
dates, separated by a dash, match any date which lies in the given
range of time.
.PP
You can also modify any absolute date by giving an error range.  An
error range consists of one of the characters
.BR + ,
.BR - ,
.BR * ,
followed by a positive number, followed by one of the unit
characters
.BR y ,
.BR m ,
.BR w ", or"
.BR d ,
specifying a unit of years, months, weeks, or days.  
.B +
increases the maximum date matched by the given interval of time,
.B - 
decreases the minimum date matched by the given interval of time, and
.B *
increases the maximum date and decreases the minimum date matched by
the given interval of time.  It is possible to give multiple error
margins, which cumulate.  Example:
.B "1/1/2001-1w+2w*3d"
.PP
You can also specify offsets relative to the current date.  An
offset is specified as one of the characters
.BR < ,
.BR > ,
.BR = ,
followed by a positive number, followed by one of the unit
characters
.BR y ,
.BR m ,
.BR w ", or"
.BR d .
.B >
matches dates which are older than the specified amount of time, an
offset which begins with the character
.B < 
matches dates which are more recent than the specified amount of time,
and an offset which begins with the character
.B =
matches points of time which are precisely the given amount of time
ago.
.SH CONFIGURATION VARIABLES