filechan - file-writing backend for InterNetNews
filechan [ -d directory ] [ -f num_fields ] [ -m mapfile ] [ -p pidfile
Filechan reads lines from standard input and copies certain fields in
each line into files named by other fields within the line. Filechan
is intended to be called by innd(8) as a channel feed. (It is not a
full exploder and does not accept commands; see newsfeeds(5) for a
description of the difference, and buffchan(8) for an exploder pro-
Filechan input is interpreted as a sequence of lines. Each line con-
tains a fixed number of initial fields, followed by a variable number
of filename fields. All fields in a line are separated by whitespace.
The default number of initial fields is one.
For each line of input, filechan writes the initial fields, separated
by whitespace and followed by a newline, to each of the files named in
the filename fields. When writing to a file, filechan opens it in
append mode and tries to lock it and change the ownership to the user
and group who owns the directory where the file is being written.
Because the time window in which a file is open is very small, compli-
cated flushing and locking protocols are not needed; a mv(1) followed
by a sleep(1) for a couple of seconds is sufficient.
The ‘‘-f’’ flag may be used to specify a different number of
By default, filechan writes its output into the directory
<pathoutgoing in inn.conf>. The ‘‘-d’’ flag may be used to
specify a directory the program should change to before start-
If the ‘‘-p’’ flag is used, the program will write a line con-
taining its process ID (in text) to the specified file.
A map file may be specified by using the ‘‘-m’’ flag. Blank
lines and lines starting with a number sign (‘‘#’’) are ignored.
All other lines should have two host names separated by a colon.
The first field is the name that may appear in the input stream;
the second field names the file to be used when the name in the
first field appears. For example, the following map file may be
used to map the short names used in the example below to the
full domain names:
# This is a comment
If filechan is invoked with ‘‘-f 2’’ and given the following input:
news/software/b/132 <email@example.com> foo uunet
news/software/b/133 <firstname.lastname@example.org> uunet munnari
comp/sources/unix/2002 <email@example.com> foo uunet munnari
Then the file foo will have these lines:
the file munnari will have these lines:
and the file uunet will have these lines:
Written by Robert Elz <firstname.lastname@example.org>, flags added by Rich $alz
<email@example.com>. This is revision 1.7, dated 2002/12/03.
buffchan(8), inn.conf(5), innd(8), newsfeeds(5).
Man(1) output converted with