#!/bin/bash # Generates a log file in current directory # from the tail end of /var/log/messages. # Note: /var/log/messages must be world readable # if this script invoked by an ordinary user. # #root chmod 644 /var/log/messages LINES=5 ( date; uname -a ) >>logfile # Time and machine name echo ---------------------------------------------------------- >>logfile tail -n $LINES /var/log/messages | xargs | fmt -s >>logfile echo >>logfile echo >>logfile exit 0 # Note: # ---- # As Frank Wang points out, #+ unmatched quotes (either single or double quotes) in the source file #+ may give xargs indigestion. # # He suggests the following substitution for line 15: # tail -n $LINES /var/log/messages | tr -d "\"'" | xargs | fmt -s >>logfile # Exercise: # -------- # Modify this script to track changes in /var/log/messages at intervals #+ of 20 minutes. # Hint: Use the "watch" command.