.\"
.TH MH-SEQUENCE %manext7% "%nmhdate%" MH.6.8 [%nmhversion%]
.SH NAME
-mh-sequence \- sequence specification for nmh message system
-.SH SYNOPSIS
-most
-.B nmh
-commands
+mh-sequence \- sequence specification for mh message system
.SH DESCRIPTION
A sequence (or sequence set) is a symbolic name representing a
message or collection of messages.
-.B nmh
+.B mmh
has several internally
defined sequences, as well as allowing users to define their own
sequences.
.SS "Message Specification and Pre\-Defined Message Sequences"
Most
-.B nmh
+.B mmh
commands accept a `msg' or `msgs' specification, where
`msg' indicates one message and `msgs' indicates one or more messages.
To designate a message, you may use either its number (e.g., 1, 10, 234)
-or one of these \*(lqreserved\*(rq message names:
+or one of these `reserved' message names:
.PP
.RS 5
.nf
.ta +\w'\fIName\fP 'u
-.I Name Description
-first the first message in the folder
-last the last message in the folder
-cur the most recently accessed message
-prev the message numerically preceding \*(lqcur\*(rq
-next the message numerically following \*(lqcur\*(rq
+.I "Name Description
+f the first message in the folder
+p the message numerically preceding `c'
+c the most recently accessed message
+n the message numerically following `c'
+l the last message in the folder
.fi
.RE
.PP
-In commands that take a `msg' argument, the default is \*(lqcur\*(rq.
-As a shorthand, \*(lq\&.\*(rq is equivalent to \*(lqcur\*(rq.
+In commands that take a `msg' argument, the default is `c'.
.PP
For example: In a folder containing five messages numbered 5, 10, 94, 177
-and 325, \*(lqfirst\*(rq is 5 and \*(lqlast\*(rq is 325. If \*(lqcur\*(rq
-is 94, then \*(lqprev\*(rq is 10 and \*(lqnext\*(rq is 177.
+and 325, `f' is 5 and `l' is 325. If `c'
+is 94, then `p' is 10 and `n' is 177.
.PP
The word `msgs' indicates that one or more messages may be specified.
Such a specification consists of one message designation or of several
message designations separated by spaces. A message designation consists
either of a message name as defined above, or a message range.
.PP
-A message range is specified as \*(lqname1\-name2\*(rq or
-\*(lqname:n\*(rq, where `name', `name1' and `name2' are message names,
-and `n' is an integer.
+A message range is specified as `name1\-name2' or
+`name:i', where `name', `name1' and `name2' are message names,
+and `i' is an integer.
.PP
-The specification \*(lqname1\-name2\*(rq designates all currently existing
-messages from `name1' to `name2' inclusive. The \*(lqreserved\*(rq
-message name \*(lqall\*(rq is a shorthand for the message range
-\*(lqfirst\-last\*(rq.
+The specification `name1\-name2' designates all currently existing
+messages from `name1' to `name2' inclusive. The `reserved'
+message name `a' (``all'') is a shorthand for the message range
+`f\-l'.
.PP
-The specification \*(lqname:n\*(rq designates up to `n' messages.
+.RS 5
+.nf
+.ta +\w'\fIName\fP 'u
+.I "Name Description
+a all messages in the folder (i.e. `f\-l')
+.fi
+.RE
+.PP
+The specification `name:i' designates up to `i' messages.
These messages start with `name' if `name' is a message number or one of
-the reserved names \*(lqfirst\*(rq \*(lqcur\*(rq, or \*(lqnext\*(rq, The
-messages end with `name' if `name' is \*(lqprev\*(rq or \*(lqlast\*(rq.
-The interpretation of `n' may be overridden by preceding `n' with a
-plus or minus sign; `+n' always means up to `n' messages starting with
-`name', and `\-n' always means up to `n' messages ending with `name'.
+the reserved names `f' `c', or `n', The
+messages end with `name' if `name' is `p' or `l'.
+The interpretation of `i' may be overridden by preceding `i' with a
+plus or minus sign; `+i' always means up to `i' messages starting with
+`name', and `\-i' always means up to `i' messages ending with `name'.
.PP
In commands which accept a `msgs' argument, the default is either
-\*(lqcur\*(rq or \*(lqall\*(rq, depending on which makes more sense
-for each command (see the individual man pages for details). Repeated
+`c' or `a', depending on which makes more sense
+for each command (see the individual man pages for details).
+.PP
+Repeated
specifications of the same message have the same effect as a single
specification of the message.
.PP
-There is also a special \*(lqreserved\*(rq message name \*(lqnew\*(rq
-which is used by the
+There is also a special `reserved' message name `b' (``beyond'')
+which can be used with the
.B mhpath
-command.
+command. It refers to the next (not yet used) message number
+after `l'.
+.PP
+.RS 5
+.nf
+.ta +\w'\fIName\fP 'u
+.I "Name Description
+b the next message number beyond `l'
+.fi
+.RE
.SS "User\-Defined Message Sequences"
-In addition to the \*(lqreserved\*(rq (pre-defined) message names given
+In addition to the `reserved' (pre-defined) message names given
above,
-.B nmh
+.B mmh
supports user-defined sequence names. User-defined
sequences allow the
-.B nmh
+.B mmh
user a tremendous amount of power in dealing
with groups of messages in the same folder by allowing the user to bind
a group of messages to a meaningful symbolic name.
.PP
The name used to denote a message sequence must consist of an alphabetic
character followed by zero or more alphanumeric characters, and can not
-be one of the \*(lqreserved\*(rq message names above. After defining a
+be one of the `reserved' message names above. After defining a
sequence, it can be used wherever an
-.B nmh
+.B mmh
command expects a `msg' or
`msgs' argument.
.PP
Some forms of message ranges are allowed with user-defined sequences.
-The specification \*(lqname:n\*(rq may be used, and it designates up
-to the first `n' messages (or last `n' messages for `\-n') which are
+The specification `name:i' may be used, and it designates up
+to the first `i' messages (or last `i' messages for `\-i') which are
elements of the user-defined sequence `name'.
.PP
-The specifications \*(lqname:next\*(rq and \*(lqname:prev\*(rq may also
+The specifications `name:n' and `name:p' may also
be used, and they designate the next or previous message (relative to the
current message) which is an element of the user-defined sequence `name'.
-The specifications \*(lqname:first\*(rq and \*(lqname:last\*(rq are
-equivalent to \*(lqname:1\*(rq and \*(lqname:\-1\*(rq, respectively. The
-specification \*(lqname:cur\*(rq is not allowed (use just \*(lqcur\*(rq
-instead). The syntax of these message range specifications is subject
+The specifications `name:f' and `name:l' are
+equivalent to `name:1' and `name:\-1', respectively. The
+specification `name:c' is not allowed (use just `c' instead).
+Note: The syntax of these message range specifications is subject
to change in the future.
.PP
User-defined sequence names are specific to each folder. They are
and
.B mark
commands.
-.PP
+
.SS "Public and Private User-Defined Sequences"
There are two varieties of user-defined sequences:
public and private. Public sequences of a folder are accessible to any
-.B nmh
+.B mmh
user that can read that folder. They are kept in each folder
-in the file determined by the \*(lqMh\-Sequences\*(rq profile entry
+in the file determined by the `Mh\-Sequences' profile entry
(default is
.IR \&.mh_sequences ).
Private sequences are accessible
only to the
-.B nmh
+.B mmh
user that defined those sequences and are kept in
the user's
-.B nmh
+.B mh
context file.
.PP
In general, the commands that create sequences (such as
.BR mark )
will create public sequences if the folder for which
the sequences are being defined is writable by the
-.B nmh
+.B mmh
user.
For most commands, this can be overridden by using the switches
.B \-public
and
.BR \-private .
But if the folder is read\-only, or if
-the \*(lqMh\-Sequences\*(rq profile entry is defined but empty, then
+the `Mh\-Sequences' profile entry is defined but empty, then
\fIprivate\fR sequences will be created instead.
.SS "Sequence Negation"
-.B Nmh
-provides the ability to select all messages not elements of a
-user-defined sequence. To do this, the user should define the entry
-\*(lqSequence\-Negation\*(rq in the
-.B nmh
-profile file; its value
-may be any string. This string is then used to preface an existing
-user-defined sequence name. This specification then refers to those
-messages not elements of the specified sequence name. For example, if
-the profile entry is:
+.B Mmh
+provides the ability to select all messages
+.B not
+elements of a user-defined sequence.
+A special string is used to preface an existing user-defined
+sequence name. This specification then refers to those
+messages not elements of the specified sequence name.
+The default negation prefix is the exlamation mark `!',
+but it may be change to any string, by defining the entry
+`Sequence\-Negation' in the
+.B mmh
+profile file.
+For example, if the profile entry is:
.PP
.RS 5
Sequence\-Negation: not
.RE
.PP
then anytime an
-.B nmh
-command is given \*(lqnotfoo\*(rq as a `msg' or
+.B mmh
+command is given `notfoo' as a `msg' or
`msgs' argument, it would substitute all messages that are not elements
-of the sequence \*(lqfoo\*(rq.
+of the sequence `foo'.
.PP
Obviously, the user should beware of defining sequences with names that
-begin with the value of the \*(lqSequence\-Negation\*(rq profile entry.
+begin with the value of the `Sequence\-Negation' profile entry.
+The default value `!' was chosen due to its similar meaning in the C
+programming language, and because it cannot be part of a user-defined
+sequence. But if your shell provides history expansion,
+you might need to quote the exlamation mark (prefix it with a backslash).
+.PP
+To deactivate the negation mechanism, define Sequence\-Negation in your
+profile to an empty value.
.SS "The Previous Sequence"
-.B Nmh
+.B Mmh
provides the ability to remember the `msgs' or `msg' argument
last given to an
-.B nmh
-command. The entry \*(lqPrevious\-Sequence\*(rq
+.B mmh
+command. The entry `Previous\-Sequence'
should be defined in the
-.B nmh
+.B mmh
profile; its value should be a sequence
name or multiple sequence names separated by spaces. If this entry
-is defined, when when an
-.B nmh
+is defined, when an
+.B mmh
command finishes, it will define the
sequence(s) named in the value of this entry to be those messages that
were specified to the command. Hence, a profile entry of
.RE
.PP
directs any
-.B nmh
+.B mmh
command that accepts a `msg' or `msgs' argument to
-define the sequence \*(lqpseq\*(rq as those messages when it finishes.
+define the sequence `pseq' as those messages when it finishes.
.PP
.BR Note :
there can be a performance penalty in using the
-\*(lqPrevious\-Sequence\*(rq facility. If it is used,
+`Previous\-Sequence' facility. If it is used,
.B all
-.B nmh
+.B mmh
programs have to write the sequence information to the
.I \&.mh_sequences
file for the folder each time they run. If the
-\*(lqPrevious\-Sequence\*(rq profile entry is not included, only
+`Previous\-Sequence' profile entry is not included, only
.B pick
and
.B mark
file.
.SS "The Unseen Sequence"
-Finally, many users like to indicate which messages have not been
-previously seen by them. The commands
+Finally, the unseen sequence indicates which messages have not been
+previously seen by the user.
+The commands
.BR inc ,
.BR rcvstore ,
.BR show ,
-.BR mhshow ,
and
.B flist
-honor the profile entry
-\*(lqUnseen\-Sequence\*(rq to support this activity. This entry
-in the
-.I .mmh/profile
-should be defined as one or more sequence
-names separated by spaces. If there is a value for
-\*(lqUnseen\-Sequence\*(rq in the profile, then whenever new messages
-are placed in a folder (using
+honor the sequence.
+Whenever new messages are placed in a folder (using
.B inc
or
.BR rcvstore ),
-the new messages will also be added to all the sequences named in this
-profile entry. For example, a profile entry of
-.PP
-.RS 5
-Unseen\-Sequence: unseen
+the new messages will also be added to the unseen sequence.
.RE
.PP
-directs
-.B inc
-to add new messages to the sequence \*(lqunseen\*(rq.
-Unlike the behavior of the \*(lqPrevious\-Sequence\*(rq entry in the
-profile, however, the sequence(s) will
+.BR inc ,
+for example,
+adds new messages to the unseen sequence.
+Unlike the behavior of the previous sequence, however,
+the unseen sequence will
.B not
be zeroed by
.BR inc .
.PP
Similarly, whenever
.BR show ,
-.BR mhshow ,
.BR next ,
or
.B prev
-displays a message, that message will be removed from
-any sequences named by the \*(lqUnseen\-Sequence\*(rq entry in the
-profile.
+display a message, that message will be removed from
+the unseen sequence.
+.PP
+The default unseen sequence is named `u'.
+To change, define a `Unseen\-Sequence' entry in your profile.
+It may also contain multiple sequence names, separated by spaces.
+In this case, anything that applied to a single unseen sequence,
+applies to multiple ones, too.
+.PP
+The unseen sequence mechanism is automatically activated.
+To deactivate it, define the `Unseen\-Sequence' entry
+in your profile with an empty value.
+
.SH FILES
.fc ^ ~
projects / mmh / blobdiff