pullnews (1) - Linux Manuals

pullnews: Pull news from multiple news servers and feed it to another

Command to display pullnews manual in Linux: $ man 1 pullnews

NAME

pullnews - Pull news from multiple news servers and feed it to another

SYNOPSIS

pullnews [-BhnOqRx] [-a hashfeed] [-b fraction] [-c config] [-C width] [-d level] [-f fraction] [-F fakehop] [-g groups] [-G newsgroups] [-H headers] [-k checkpt] [-l logfile] [-m header_pats] [-M num] [-N timeout] [-p port] [-P hop_limit] [-Q level] [-r file] [-s to-server[:port]] [-S max-run] [-t retries] [-T connect-pause] [-w num] [-z article-pause] [-Z group-pause] [from-server ...]

REQUIREMENTS

The "Net::NNTP" module must be installed. This module is available as part of the libnet distribution and comes with recent versions of Perl. For older versions of Perl, you can download it from <http://www.cpan.org/>.

DESCRIPTION

pullnews reads a config file in the running user's home directory (normally called ~/.pullnews) and connects to the upstream servers given there as a reader client. By default, it connects to all servers listed in the configuration file, but you can limit pullnews to specific servers by listing them on the command line: a whitespace-separated list of server names can be specified, like from-server for one of them. For each server it connects to, it pulls over articles and feeds them to the destination server via the IHAVE or POST commands. This means that the system pullnews is run on must have feeding access to the destination news server.

pullnews is designed for very small sites that do not want to bother setting up traditional peering and is not meant for handling large feeds.

OPTIONS

-a hashfeed

This option is a deterministic way to control the flow of articles and to split a feed. The hashfeed parameter must be in the form "value/mod" or "start-end/mod". The Message-ID of each article is hashed using MD5, which results in a 128-bit hash. The lowest 32 bits are then taken by default as the hashfeed value (which is an integer). If the hashfeed value modulus "mod" plus one equals "value" or is between "start" and "end", pullnews will feed the article. All these numbers must be integers.

For instance:

    pullnews -a 1/2      Feeds about 50% of all articles.
    pullnews -a 2/2      Feeds the other 50% of all articles.

Another example:

    pullnews -a 1-3/10   Feeds about 30% of all articles.
    pullnews -a 4-5/10   Feeds about 20% of all articles.
    pullnews -a 6-10/10  Feeds about 50% of all articles.

You can use an extended syntax of the form "value/mod:offset" or "start-end/mod:offset" (using an underscore "_" instead of a colon ":" is also recognized). As MD5 generates a 128-bit return value, it is possible to specify from which byte-offset the 32-bit integer used by hashfeed starts. The default value for "offset" is ":0" and thirteen overlapping values from ":0" to ":12" can be used. Only up to four totally independent values exist: ":0", ":4", ":8" and ":12".

Therefore, it allows to a generate a second level of deterministic distribution. Indeed, if pullnews feeds "1/2", it can go on splitting thanks to "1-3/9:4" for instance. Up to four levels of deterministic distribution can be used.

The algorithm is compatible with the one used by Diablo 5.1 and up.

-b fraction

Backtrack on server numbering reset. Specify the proportion (0.0 to 1.0) of a group's articles to pull when the server's article number is less than our high for that group. When fraction is 1.0, pull all the articles on a renumbered server. The default is to do nothing.

-B

Feed is header-only, that is to say pullnews only feeds the headers of the articles, plus one blank line. It adds the Bytes: header field if the article does not already have one, and keeps the body only if the article is a control article.

-c config

Normally, the config file is stored in ~/.pullnews for the user running pullnews. If -c is given, config will be used as the config file instead. This is useful if you're running pullnews as a system user on an automated basis out of cron rather than as an individual user.

See ``CONFIG FILE'' below for the format of this file.

-C width

Use width characters per line for the progress table. The default value is 50.

-d level

Set the debugging level to the integer level; more debugging output will be logged as this increases. The default value is 0.

-f fraction

This changes the proportion of articles to get from each group to fraction and should be in the range 0.0 to 1.0 (1.0 being the default).

-F fakehop

Prepend fakehop as a host to the Path: header of articles fed.

-g groups

Specify a collection of groups to get. groups is a list of newsgroups separated by commas (only commas, no spaces). Each group must be defined in the config file, and only the remote hosts that carry those groups will be contacted. Note that this is a simple list of groups, not a wildmat expression, and wildcards are not supported.

-G newsgroups

Add the comma-separated list of groups newsgroups to each server in the configuration file (see also -g and -w).

-h

Print a usage message and exit.

-H headers

Remove these named headers (colon-separated list) from fed articles.

-k checkpt

Checkpoint (save) the config file every checkpt articles (default is 0, that is to say at the end of the session).

-l logfile

Log progress/stats to logfile (default is "stdout").

-m header_pats

Feed an article based on header matching. The argument is a number of whitespace-separated tuples (each tuple being a colon-separated header and regular expression). For instance:

    -m "Hdr1:regexp1 !Hdr2:regexp2 #Hdr3:regexp3 !#Hdr4:regexp4"

specifies that the article will be passed only if the "Hdr1:" header matches "regexp1" and the "Hdr2:" header does not match "regexp2". Besides, if the "Hdr3:" header matches "regexp3", that header is removed; and if the "Hdr4:" header does not match "regexp4", that header is removed.

-M num

Specify the maximum number of articles (per group) to process. The default is to process all new articles. See also -f.

-n

Do nothing but read articles -- does not feed articles downstream, writes no rnews file, does not update the config file.

-N timeout

Specify the timeout length, as timeout seconds, when establishing an NNTP connection.

-O

Use an optimized mode: pullnews checks whether the article already exists on the downstream server, before downloading it. It may help for huge articles or a slow link to upstream hosts.

-p port

Connect to the destination news server on a port other than the default of 119. This option does not change the port used to connect to the source news servers.

-P hop_limit

Restrict feeding an article based on the number of hops it has already made. Count the hops in the Path: header (hop_count), feeding the article only when hop_limit is "+num" and hop_count is more than num; or hop_limit is "-num" and hop_count is less than num.

-q

Print out less status information while running.

-Q level

Set the quietness level ("-Q 2" is equivalent to "-q"). The higher this value, the less gets logged. The default is 0.

-r file

Rather than feeding the downloaded articles to a destination server, instead create a batch file that can later be fed to a server using rnews. See rnews(1) for more information about the batch file format.

-R

Be a reader (use MODE READER and POST commands) to the downstream server. The default is to use the IHAVE command.

-s to-server[:port]

Normally, pullnews will feed the articles it retrieves to the news server running on localhost. To connect to a different host, specify a server with the -s flag. You can also specify the port with this same flag or use -p.

-S max-run

Specify the maximum time max-run in seconds for pullnews to run.

-t retries

The maximum number (retries) of attempts to connect to a server (see also -T). The default is 0.

-T connect-pause

Pause connect-pause seconds between connection retries (see also -t). The default is 1.

-w num

Set each group's high water mark (last received article number) to num. If num is negative, calculate Current+num instead (i.e. get the last num articles). Therefore, a num of 0 will re-get all articles on the server; whereas a num of "-0" will get no old articles, setting the water mark to Current (the most recent article on the server).

-x

If the -x flag is used, an Xref: header is added to any article that lacks one. It can be useful for instance if articles are fed to a news server which has xrefslave set in inn.conf.

-z article-pause

Sleep article-pause seconds between articles. The default is 0.

-Z group-pause

Sleep group-pause seconds between groups. The default is 0.

CONFIG FILE

The config file for pullnews is divided into blocks, one block for each remote server to connect to. A block begins with the host line (which must have no leading whitespace) and contains just the hostname of the remote server, optionally followed by authentication details (username and password for that server). Note that authentication details can also be provided for the downstream server (a host line could be added for it in the configuration file, with no newsgroup to fetch).

Following the host line should be one or more newsgroup lines which start with whitespace followed by the name of a newsgroup to retrieve. Only one newsgroup should be listed on each line.

pullnews will update the config file to include the time the group was last checked and the highest numbered article successfully retrieved and transferred to the destination server. It uses this data to avoid doing duplicate work the next time it runs.

The full syntax is:

    <host> [<username> <password>]
            <group> [<time> <high>]
            <group> [<time> <high>]

where the <host> line must not have leading whitespace and the <group> lines must.

A typical configuration file would be:

    # Format group date high
    data.pa.vix.com
            rec.bicycles.racing 908086612 783
            rec.humor.funny 908086613 18
            comp.programming.threads
    nnrp.vix.com pull sekret
            comp.std.lisp

Note that an earlier run of pullnews has filled in details about the last article downloads from the two rec.* groups. The two comp.* groups were just added by the user and have not yet been checked.

The nnrp.vix.com server requires authentication, and pullnews will use the username "pull" and the password "sekret".

FILES

pathbin/pullnews: The Perl script itself used to pull news from upstream servers and feed it to another news server.
~/.pullnews: The default config file. It is in the running user's home directory.

HISTORY

pullnews was written by James Brister for INN. The documentation was rewritten in POD by Russ Allbery <eagle [at] eyrie.org>.

Geraint A. Edwards greatly improved pullnews, adding no more than 16 new recognized flags, fixing some bugs and integrating the backupfeed contrib script by Kai Henningsen, adding again 6 other flags.

$Id: pullnews.pod 9768 2014-12-07 21:22:57Z iulius $