jbuck@epimass.EPI.COM (Joe Buck) (06/29/88)
Posting-number: Volume 3, Issue 66
Submitted-by: "Joe Buck" <jbuck@epimass.EPI.COM>
Archive-name: newspaths
#! /bin/sh
# This is a shell archive, meaning:
# 1. Remove everything above the #! /bin/sh line.
# 2. Save the resulting text in a file.
# 3. Execute the file with /bin/sh (not csh) to create the files:
# README
# newspaths
# newspaths.1
# twoway
# This archive created: Tue Jun 28 19:52:10 1988
export PATH; PATH=/bin:$PATH
if test -f 'README'
then
echo shar: will not over-write existing file "'README'"
else
cat << \SHAR_EOF > 'README'
Here's the stuff I used to generate the map in article <2249@epimass.epi.com>.
Have fun. If only it drew the maps too -- maybe Brian Reid can attach
it to something.
- Joe
SHAR_EOF
fi # end of overwriting check
if test -f 'newspaths'
then
echo shar: will not over-write existing file "'newspaths'"
else
cat << \SHAR_EOF > 'newspaths'
#! /usr/bin/perl
# Copyright 1988 by Joseph T. Buck, jbuck@epimass.epi.com.
# You may freely use and copy this program as long as you
# leave my name here.
# newspaths -- news path statistics gatherer
# This perl program scans through all the news on your spool
# (using the history file to find the articles) and prints
# out a sorted list of frequencies that each pair of hosts
# appears in the Path: headers. That is, it determines how,
# on average, your news gets to you.
#
# If an argument is given, it is the name of a previous output
# of this program. The figures are read in, and host pairs
# from articles newer than the input file are added in.
# So that this will work, the first line of the output of the
# program is of the form
# Last-ID: <5679@chinet.UUCP>
# (without the # sign). It records the last Message-ID in the
# history file; to add new articles, we skip in the history file
# until we find it.
$skip = 0;
if ($#ARGV >= 0) {
$ofile = $ARGV[0];
die "Can't open $ofile!\n" unless open (of, $ofile);
# First line must contain last msgid to use.
$_ = <of>;
($key, $last_id) = split (' ');
die "Invalid input file format!\n" if ($key ne "Last-ID:");
$skip = 1;
# Read in the old file.
while (<of>) {
($cnt, $pair) = split(' ');
$pcount{$pair} = $cnt;
}
}
# Let's go.
die "Can't open history file!\n" unless open (hist, "/usr/lib/news/history");
die "Can't cd to news spool directory!\n" unless chdir ("/usr/spool/news");
$np = $nlocal = 0;
while (<hist>) {
#
# $_ contains a line from the history file. Parse it.
# Skip it if the article has been cancelled or expired
# If the $skip flag is true, we skip until we have the right msgid
#
($id, $date, $time, $file) = split (' ');
next if ($file eq 'cancelled' || $file eq '');
if ($skip) {
if ($id eq $last_id) { $skip = 0; }
next;
}
#
# format of field is like comp.sources.unix/2345 . Get ng and filename.
#
($ng, $n) = split (/\//, $file);
$file =~ tr%.%/%;
#
# The following may be used to skip any local groups. Here, we
# skip group names beginning with "epi" or "su". Change to suit taste.
#
next if $ng =~ /^epi|^su/;
next unless open (art, $file); # skip if cannot open file
#
# Article OK. Get its path.
while (<art>) {
($htype, $hvalue) = split (' ');
if ($htype eq "Path:") {
# We have the path, in hvalue.
$np++;
@path = split (/!/, $hvalue);
# Handle locally posted articles.
if ($#path < 2) { $nlocal++; last;}
# Create and count pairs.
for ($i = 0; $i < $#path - 1; $i++) {
$pair = $path[$i] . "!" . $path[$i+1];
$pcount{$pair} += 1;
}
last;
}
}
}
# Make sure print message comes out before sort data.
$| = 1;
print "Last-ID: $id\n";
$| = 0;
# write the data out, sorted. Open a pipe.
die "Can't exec sort!\n" unless open (sort, "|sort -nr");
while (($pair, $n) = each (pcount)) {
printf sort ("%6d %s\n", $n, $pair);
}
close sort;
SHAR_EOF
fi # end of overwriting check
if test -f 'newspaths.1'
then
echo shar: will not over-write existing file "'newspaths.1'"
else
cat << \SHAR_EOF > 'newspaths.1'
.TH NEWSPATHS 1 5/31/88
.SH "NAME"
newspaths \- collect host connectivity information from Usenet articles
.SH "SYNOPSIS"
.B newspaths
[
.I prev_out
]
.SH "DESCRIPTION"
.I Newspaths
scans the history file, in
.IR /usr/lib/news/history ,
using it to locate Usenet articles. For each article, the Path:
header is read, and split up into its constituent host pairs.
An associative array keeps track of how many times each pair of
hosts appears in a Path: header. Every article in the history file is
scanned.
.PP
The output format consists of the last Message-ID in the history file,
followed by a sorted list of host pairs and counts. Here's a sample:
.sp
.nf
Last-ID: <24524@oliveb.olivetti.com>
42814 epimass!pyramid
22610 pyramid!ames
12824 pyramid!decwrl
7854 ames!mailrus
5426 oliveb!ames
5391 ames!pasteur
5212 decwrl!ucbvax
< lots more >
.fi
.PP
If an input file argument is given, it should be the name of a previous
output of
.IR newspaths .
The file and counts are read in, and the history file is scanned until
the Last-ID is found. Normal processing begins with the next
article given in the history file. The idea is to be able to continue
to accumulate the counts over long periods of time (despite
.I expire
runs) and to count each article only once. It is an error if the
given Message-ID is not found in the history file.
.SH "SUGGESTED USE"
Every night, from
.IR cron ,
do
.nf
newspaths old-output > new-output
mv new-output old-output
.fi
.sp
After 1 month of operation at
.I epimass ,
the resulting output is 135K bytes long.
.SH AUTHOR
Joseph T. Buck, jbuck@epimass.epi.com
SHAR_EOF
fi # end of overwriting check
if test -f 'twoway'
then
echo shar: will not over-write existing file "'twoway'"
else
cat << \SHAR_EOF > 'twoway'
#! /usr/bin/perl
#
# twoway -- convert unidirectional counts from "newspaths" into two-way counts
# Usage: twoway file
# where file is an output from "newspaths".
$_ = <>; # Skip the Last-ID: line
while (<>) {
($n, $pair) = split (' ');
($a, $b) = split (/!/, $pair);
if ($a gt $b) { $pair = $b . "!" . $a; } # alphabetical order
$count{$pair} += $n;
}
die "Can't exec sort!\n" unless open (sort, "|sort -nr");
while (($pair, $n) = each (count)) {
printf sort ("%5d %s\n", $n, $pair);
}
close sort;
SHAR_EOF
chmod +x 'twoway'
fi # end of overwriting check
# End of shell archive
exit 0
--
- Joe Buck {uunet,ucbvax,pyramid,<smart-site>}!epimass.epi.com!jbuck
jbuck@epimass.epi.com Old Arpa mailers: jbuck%epimass.epi.com@uunet.uu.net
If you leave your fate in the hands of the gods, don't be
surprised if they have a few grins at your expense. - Tom Robbins