NAME
ezmlm-archive - create thread and author index for a
mailing list archive
SYNOPSIS
ezmlm-archive [ -cCFTvV ][ -f
msg1 ] ][ -t msg2 ] dir
DESCRIPTION
ezmlm-archive reads the index files from
a message archive, and creates a subject index, a collection of
subject files, and a collection of author files. These files are
suitable as an index for WWW access to, and navigation through a
mailing list archive by ezmlm-cgi(1).
The index files read are created by ezmlm-idx(1)
on a per-list basis and by ezmlm-send(1)
on a per-message archive for a indexed list.
The output files created are:
- dir/archive/threads/yyyymm
- The thread index. It contains one line per subject, starting
with the number of the first message with that subject within the
set investigated, ``:'', a 20 character subject hash, blank,
``[n]'' where ``n'' is the number of messages in the thread, blank,
and the subject. The file ``yyyymm'' contains entries for all
threads that have messages in the month ``yyyymm'' or that have
messages both before and after that month. The subject hash is a
key to the subject files; the message number is a key to the index
file. The lines are in ascending order by message number when the
index is created de novo on an existing archive. When the
messages are added one-by-one as in normal archive operation, ``n''
is the number of message in the thread for the particular
month and the order is in reverse of latest message, i.e. the
last extended thread is shown last. The message number accompanying
a thread is always a message within the thread. It is the first in
archives created on existing lists, and the last message in
incrementally created archives. Use the corresponding subject index
file to get a list of all messages in the thread in ascending
order.
- dir/archive/subjects/xx/yyyyyyyyyyyyyyyyyy
- A subject file. The first line is the subject hash, a space,
and the subject. This is followed by one line per message with this
subject, in the format message number, ``:'', date (yyyymm), ``:'',
author hash, blank, author from line. The lines are sorted by
message number. The author hash is a key to the author files; the
message number is a key to the index file. The file in the example
would be for the subject hash ``xxyyyyyyyyyyyyyyyyyy''.
- dir/archive/authors/xx/yyyyyyyyyyyyyyyyyy
- An author file. The first line is the author hash, a space, and
the author from line. This is followed by one line per message with
this author, in the format message number, ``:'', date (yyyymm),
``:'', subject hash, blank, subject. The lines are sorted by
message number. The subject hash is a key to the subject files; the
message number is a key to the index file. The file in the example
would be for the author hash ``xxyyyyyyyyyyyyyyyyyy''.
dir/archnum keeps track of the last message
processed. Normally, ezmlm-archive will process entries for
messages from one above the contents of this file up to an
including the message number in dir/num.
OPTIONS
ezmlm-archive writes messages in a
crash-proof manner when run in normal mode. When overriding the
normal message range with any of the options listed, the normal
of
the output files is suppressed for efficiency. Should the computer
crash during this time the state of the indices is not defined. Use
the -s option in the (extremely rare) cases where this would
be a problem.
- -c
- Create a new index. This overrides dir/archnum
causing ezmlm-archive to start with the first message in the
archive. Synonym for -f0. NOTE:
ezmlm-archive does not remove files in the index. While it
will overwrite/update old files it will not remove files that are
obsolete for other reasons.
- -C
- (Default.) Process entries starting with the message after the
message listed in dir/archnum.
- -f msg1
- Process messages from the archive section (set of 100 messages)
containing message msg1. This is useful if you have removed
part of the archive, as it will shorten processing time and
decrease memory use. NOTE: ezmlm-archive does not
remove files in the index. While it will overwrite/update old files
it will not remove files that are obsolete for other reasons. The
number of messages per thread will be incorrect when using of the
-f and -t switches leads to partial re-indexing of
already indexed messages.
- -F
- (Default.) Do not change the starting message from the default
(see -C).
- -s
- Always sync files.
- -S
- (Default.) Sync files, except when on of the message range
modifying options is used.
- -t msg2
- Process messages to message msg2 instead of the last
message in the archive. Again, files written are corrected, but
other files are not explicitly removed.
- -T
- (Default.) Process entries for messages up to the last message
in the archive.
- -v
- Display ezmlm-archive version info.
- -V
- Display ezmlm-archive version info.
MEMORY USAGE
ezmlm-archive stores its linked lists
in memory. On at 32-bit architecture, it uses 12 bytes per message,
28 bytes per thread (plus one copy of the subject), and 20 bytes
per author (plus one copy of the author from line).
In normal list use, it processes only at most a few messages at
a time, but for initial processing of a large archive, considerable
amounts of memory may be used. Assuming 40 bytes for subject/from
line, 5 messages per thread, 100,000 messages, and 1000 authors,
this is 2.5 MB. For 1,000,000 messages this is about 20 MB.
Thus, for large archives, it may be useful to use the -t
switch to process the archive in multiple subsets, starting with
e.g. the first 100,000, then the next, and so on.
SEE ALSO
ezmlm-cgi(1),
ezmlm-idx(1),
ezmlm-send(1),
ezmlm(5)