BUFFCHAN(8) BUFFCHAN(8)

NAME buffchan - buffered file-writing backend for InterNetNews

SYNOPSIS buffchan [ -b ] [ -c lines ] [ -C seconds ] [ -d directory ] [ -f num_fields ] [ -m map ] [ -p pidfile ] [ -l lines ] [ -L seconds ] [ -r ] [ -s filename_format ] [ -u ]

DESCRIPTION Buffchan reads lines from standard input and copies certain fields in each line into files named by other fields within the line. Buffchan is intended to be called by innd(8) as an exploder feed.

OPTIONS -b Once buffchan opens a file it keeps it open. The input must therefore never specify more files than the number of available descriptors can keep open. If the -b flag is used, the pro- gram will allocate a buffer and attach it to the file using set- buf(3).

-c lines If the -c flag is used, buffchan will close, and re-open, a file after every lines lines are written to a file.

-C seconds Similarly, the -C flag may be used to specify that all files should be closed and re-opened every seconds seconds.

-d directory The -d flag may be used to specify a directory the program should change to before starting. If this flag is used, then the default for the -s flag is changed to be a simple %s.

-f num_fields Buffchan input is interpreted as a sequence of lines. Each line contains a fixed number of initial fields, followed by a vari- able number of filename fields. All fields in a line are sepa- rated by whitespace. The default number of initial fields is one; the -f flag may be used to specify a different number of fields.

-m map Map files specify short names as aliases for domain names; see filechan(8) for details and an example.

-p pidfile If the -p flag is used, the program will write a line con- taining its process ID (in text) to the specified file.

-l lines If the -l flag is used, buffchan will call fflush(3) after every lines lines are written to a file.

-L seconds If the -L flag is used, all files will be flushed every n seconds.

-r By default, the program sends its error messages to <pathlog in inn.conf>/errlog. To suppress this redirection and send error messages to standard error, use the -r flag.

-s filename_format After the initial fields, each remaining field names a file to write. The -s flag may be used to specify a format string that maps the field to a file name. This is a sprintf(3) format string which should have a single %s parameter which will be given the contents of a non-initial field. The default value is <pathoutgoing in inn.conf>/%s. See the description of this flag in filechan(8).

-u If the -u flag is used, the program will request unbuffered output.

Buffchan can be invoked as an exploder feed (see newsfeeds(5)). As such, if a line starts with an exclamation point it will be treated as a command. There are three commands, described below:

flush The flush command closes and re-opens all open files; flush xxx which flushes only the specified site. These are analogous to the ctlinnd(8) flush command, and can be achieved by doing a send "flush xxx" command. Applications can tell that the flush has completed by renaming the file before issuing the command; buffchan has completed the command when the original filename re-appears. If <$ac_cv_func_fchmod in config.cache> is yes, then buffchan also changes the access permissions of the file from read-only for everyone to read-write for owner and group as it flushes or closes each out- put file. It will change the modes back to read-only if it re- opens the same file.

drop The drop command is similar to the flush command except that no files are re-opened. If given an argument, then the specified site is dropped, otherwise all sites are dropped. (Note that the site will be restarted if the input stream men- tions the site.) When a ctlinnd drop site command is sent, innd will automatically forward the command to buffchan for sites listed as funnels feeding into this exploder. To drop all sites, use the ctlinnd send buffchan-site drop command.

readmap The map file (specified with the -m flag) is reloaded.

HISTORY Written by Rich $alz <rsalz@uunet.uu.net> for InterNetNews. This is revision 5909, dated 2002-12-03.

SEE ALSO ctlinnd(8), filechan(8), inn.conf(5), innd(8), newsfeeds(5).

BUFFCHAN(8)