[mmh] / man / scan.man1

.\"
.\" %nmhwarning%
.\"
.TH SCAN %manext1% "%nmhdate%" MH.6.8 [%nmhversion%]
.SH NAME
scan \- produce a one line per message scan listing
.SH SYNOPSIS
.HP 5
.na
.B scan
.RI [ +folder ]
.RI [ msgs ]
.RB [ \-clear " | " \-noclear ]
.RB [ \-form
.IR formatfile ]
.RB [ \-width
.IR columns ]
.RB [ \-file
.IR filename ]
.RB [ \-version ]
.RB [ \-help ]
.ad
.SH DESCRIPTION
.B Scan
produces a one\-line\-per\-message listing of the specified
folder or messages.  Each
.B scan
line contains the message number
(name), the date, the \*(lqFrom:\*(rq field and the \*(lqSubject\*(rq field.
For example:
.PP
.RS 5
.nf
.ta \w'15+- 'u +\w'07/\|05x 'u +\w'Dcrocker  'u
15+     10/\|05 crocker nned
16\-    10/\|05 crocker message id format
18      10/\|06 brien   Re: Exit status from mkdir
19      10/\|07*brien   \*(lqscan\*(rq listing format in nmh
.fi
.RE
.PP
The `+' on message 15 indicates that it is the current message.
.PP
The `\-' on message 16 indicates that it has been replied to, as indicated
by a \*(lqReplied:\*(rq component (produced by the
.B \-annotate
switch
to the
.B repl
command).
.PP
The `*' on message 19 indicates that no \*(lqDate:\*(rq header was
present.  The time of last modification of the message is given instead.
.PP
.B Scan
actually reads each of the specified messages and parses them to extract
the desired fields.  During parsing, appropriate error messages will be
produced if there are format errors in any of the messages.
.PP
By default,
.B scan
will decode RFC-2047 (MIME) encoding in
these scan listings.
.B Scan
will only decode these fields if your
terminal can natively display the character set used in the encoding.
You should set the MM_CHARSET environment variable to your native
character set, if it is not US-ASCII.  See the mh-profile(5) man
page for details about this environment variable.
.PP
The
.B \-file
.I filename
switch allows the user to obtain a
.B scan
listing of a maildrop file as produced by
.BR packf .
This listing
includes every message in the file (you can't scan individual messages).
.PP
The switch
.B \-width
.I columns
may be used to specify the width of
the scan line.  The default is to use the width of the terminal.
.PP
If the
.B \-clear
switch is used and
.BR scan 's
output is directed
to a terminal, then
.B scan
will consult the environment variables
.B $TERM
and
.B $TERMCAP
to determine your terminal type in order
to find out how to clear the screen prior to exiting.  If the
.B \-clear
switch is used and
.BR scan 's
output is not directed to a terminal
(e.g., a pipe or a file), then
.B scan
will send a formfeed prior
to exiting.
.PP
For example, the command:
.PP
.RS 5
(scan \-clear ; show all \-show pr \-f) | lpr
.RE
.PP
produces a scan listing of the current folder, followed by a formfeed,
followed by a formatted listing of all messages in the folder, one
per page.  Omitting
.RB \*(lq "\-show\ pr\ \-f" \*(rq
will cause the messages to be
concatenated, separated by a one\-line header and two blank lines.
.PP
To override the output format used by
.BR scan ,
the
.B \-form
.I file
switch is used.  This permits individual fields of
the scan listing to be extracted with ease.
.I file
is either the name of a format file or a format string directly,
if prepended with an equal sign `='.
See
.BR mh\-format (5)
for the details.
.PP
In addition to the standard
.BR mh\-format (5)
escapes,
.B scan
also recognizes the following additional
.I component
escapes:
.PP
.RS 5
.nf
.ta \w'Dtimenow  'u +\w'Returns  'u
.I Escape       Returns Description
dtimenow        date    the current date
folder  string  the name of the current folder
.fi
.RE
.PP
If no date header is present in the message, the
.I function
escapes
which operate on
.RB { date }
will return values for the date of last
modification of the message file itself.  This feature is handy for
scanning a draft folder, as message drafts usually aren't allowed
to have dates in them.
.PP
.B scan
will update the
.B mmh
context prior to starting the listing,
so interrupting a long
.B scan
listing preserves the new context.
.B nmh
purists hate this idea.

.SH FILES
.fc ^ ~
.nf
.ta \w'%etcdir%/ExtraBigFileName  'u
^$HOME/.mmh/profile~^The user profile
.fi

.SH "PROFILE COMPONENTS"
.fc ^ ~
.nf
.ta 2.4i
.ta \w'ExtraBigProfileName  'u
^Path:~^To determine the user's mail storage
^Alternate\-Mailboxes:~^To determine the user's mailboxes
^Current\-Folder:~^To find the default current folder
.fi

.SH "SEE ALSO"
inc(1), pick(1), show(1), mh\-format(5)

.SH DEFAULTS
.nf
.RB ` +folder "' defaults to the current folder"
.RB ` msgs "' defaults to all"
.RB ` \-form "' defaulted as described above"
.RB ` \-width "' defaulted to the width of the terminal"
.fi

.SH CONTEXT
If a folder is given, it will become the current folder.

.SH BUGS
The argument to the
.B \-form
switch must be interpreted as a single
token by the shell that invokes
.BR scan .
Therefore, one must usually
place the argument to this switch inside double\-quotes.
.PP
The value of each
.I component
escape is set by
.B scan
to the
contents of the first message header
.B scan
encounters with the
corresponding component name; any following headers with the same
component name are ignored.