Pipes in syslog

You could get your syslog.conf to point to a pipe instead of the messages file and then have a job running that reads from the pipe greps out any messages you dont want and then writes any other messages to the messages file! eg :

1. Create a named pipe using mkfifo: mkfifo -p /var/adm/syslog.pipe
    
2. Make syslog.conf to points to this file (for example  /var/adm/syslog.pipe)

     *.info            |/var/adm/syslog.pipe
    

3. Relaunch syslogd:
     kill -HUP `cat /var/run/syslogd.pid`
    
4. Create processing script that read the pipe. It should run constantly and be launched from RC scripts

   #!/bin/ksh
    
   cat /var/adm/syslog.pipe | grep -v "denied update from" | while read LINE
   do
     echo $LINE >>/var/adm/denied_update.log
   done

syslog-ng has slightly different sysntax but similar capabilities