FILECHAN(8) | System Manager's Manual | FILECHAN(8) |
filechan - file-writing backend for InterNetNews
filechan [ -d directory ] [ -f 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 program.)
Filechan input is interpreted as a set of lines. Each line contains 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.
If filechan is invoked with ``-f 2'' and given the following input:
news/software/b/132 <1643@munnari.oz.au> foo uunet news/software/b/133 <102060@litchi.foo.com> uunet munnari comp/sources/unix/2002 <999@news.foo.com> foo uunet munnari
Then the file foo will have these lines:
news/software/b/132 <1643@munnari.oz.au> comp/sources/unix/2002 <999@news.foo.com>
the file munnari will have these lines:
news/software/b/133 <102060@litchi.foo.com> comp/sources/unix/2002 <999@news.foo.com>
and the file uunet will have these lines:
news/software/b/132 <1643@munnari.oz.au> news/software/b/133 <102060@litchi.foo.com> comp/sources/unix/2002 <999@news.foo.com>
Because the time window in which a file is open is very small, complicated flushing and locking protocols are not needed; a mv(1) followed by a sleep(1) for a couple of seconds is sufficient.
# This is a comment uunet:news.uu.net foo:foo.com munnari:munnari.oz.au
Written by Robert Elz <kre@munnari.oz.au>, flags added by Rich $alz <rsalz@uunet.uu.net>. This is revision 1.19, dated 1996/10/29.