SCAN (1)
produce a one line per message scan listing
SYNOPSIS
+.5i
scan
\%[+folder] \%[msgs]
\%[-clear] \%[-noclear]
\%[-form\ formatfile]
\%[-format\ string]
\%[-header] \%[-noheader]
\%[-width\ columns]
\%[-reverse] \%[-noreverse]
\%[-file filename]
\%[-version]
\%[-help]
-.5i
DESCRIPTION
Scan produces a one-line-per-message listing of the specified
folder or messages. Each scan line contains the message number
(name), the date, the \*(lqFrom:\*(rq field, the \*(lqSubject\*(rq field,
and, if room allows, some of the body of the message. For example:
+.5i
\w'15+- 'u +\w'07/\|05x 'u +\w'Dcrocker 'u
15+ 10/\|05 crocker nned\0\0\*(<<Last week I asked some of
16- 10/\|05 crocker message id format\0\0\*(<<I recommend
18 10/\|06 brien Re: Exit status from mkdir
19 10/\|07*brien \*(lqscan\*(rq listing format in nmh
-.5i
The `+' on message 15 indicates that it is the current message.
The `-' on message 16 indicates that it has been replied to, as indicated
by a \*(lqReplied:\*(rq component (produced by the `-annotate' switch
to the repl command).
The `*' on message 19 indicates that no \*(lqDate:\*(rq header was
present. The time of last modification of the message is given instead.
If there is sufficient room left on the scan line after the
subject, the line will be filled with text from the body, preceded by
<<, and terminated by >> if the body is sufficiently short. 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.
By default, scan will decode RFC-2047 (MIME) encoding in
these scan listings. 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.
The switch `-reverse', makes scan list the messages in reverse
order.
The `-file filename' switch allows the user to obtain a scan
listing of a maildrop file as produced by packf. This listing
includes every message in the file (you can't scan individual messages).
The switch `-reverse' is ignored with this option.
The switch `-width\ columns' may be used to specify the width of
the scan line. The default is to use the width of the terminal.
The `-header' switch produces a header line prior to the scan
listing. Currently, the name of the folder and the current date and
time are output (see the HISTORY section for more information).
If the `-clear' switch is used and scan's output is directed
to a terminal, then scan will consult the environment variables
$TERM and $TERMCAP to determine your terminal type in order
to find out how to clear the screen prior to exiting. If the `-clear'
switch is used and scan's output is not directed to a terminal
(e.g., a pipe or a file), then scan will send a formfeed prior
to exiting.
For example, the command:
(scan -clear -header; show all -show pr -f) | lpr
produces a scan listing of the current folder, followed by a formfeed,
followed by a formatted listing of all messages in the folder, one
per page. Omitting `-show\ pr\ -f' will cause the messages to be
concatenated, separated by a one-line header and two blank lines.
To override the output format used by scan, the `-format\ string'
or `-form\ file' switches are used. This permits individual fields of
the scan listing to be extracted with ease. The string is simply a format
string and the file is simply a format file. See mh-format(5)
for the details.
In addition to the standard mh-format(5) escapes, scan
also recognizes the following additional component escapes:
\w'Dtimenow 'u +\w'Returns 'u
Escape Returns Description
body string the (compressed) first part of the body
dtimenow date the current date
folder string the name of the current folder
If no date header is present in the message, the function escapes
which operate on {date\|} will return values for the date of last
modification of the message file itself. This feature is handy for
scanning a draft folder, as message drafts usually aren't allowed
to have dates in them.
scan will update the nmh context prior to starting the listing,
so interrupting a long scan listing preserves the new context.
nmh purists hate this idea.
^$HOME/.mh\(ruprofile~^The user profile
^Path:~^To determine the user's nmh directory
^Alternate-Mailboxes:~^To determine the user's mailboxes
^Current-Folder:~^To find the default current folder
inc(1), pick(1), show(1), mh-format(5)
`+folder' defaults to the current folder
`msgs' defaults to all
`-format' defaulted as described above
`-noheader'
`-width' defaulted to the width of the terminal
If a folder is given, it will become the current folder.
Prior to using the format string mechanism, `-header' used to generate
a heading saying what each column in the listing was. Format strings
prevent this from happening.
The argument to the `-format' switch must be interpreted as a single
token by the shell that invokes scan. Therefore, one must usually
place the argument to this switch inside double-quotes.
The value of each component escape is set by scan to the
contents of the first message header scan encounters with the
corresponding component name; any following headers with the same
component name are ignored.
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