A co-worker is learning Perl through self study. He's borrowed my Llama book for a start. As part of the learning I've agreed to provide him with "real world" exercises.

Do the following exercises for analysing *nix log files seem reasonable to you? He seems to be having trouble with them. He does know about split and join and the basics of array and hash use. A few hundred lines of messages was snipped and dropped into the directory he's using for the exercises. 

Problem #1:
    Read the log file messages.  Print a list of:

        Count TimeStamp

    I'm looking for the number of log messages per hour of the day.  S
+omething like

[download]
    144 Apr 10 04:00
    280 Apr 10 05:00

Problem #2
   Read the log file messages instead of counting the number of messag
+es per hour,
   count the number of instances for each message.  Something like

   2    syslogd 1.4.1: restart (remote reception).
   189  ntpd[3216]: synchronized to 192.168.1.15, stratum 3
   1880 last message repeated 9 times


Problem #3
   Modify solution to problem #2 so that "last message repeated X time
+s" adds to the count of the last message

Problem #4
   Modify solution to problem #3 to ignore the PID   Meaning:

   ntpd[3216]: synchronized to 192.168.1.15, stratum 3
     will report as
   ntpd: synchronized to 192.168.1.15, stratum 3

Problem #5
   Modify solution to problem #4 to report on activity per hour

   Apr 10 04:00 - XXXXX
       xxxx ntpd: synchronized to  192.168.1.15, stratum 3
       xxxx syslogd 1.4.1: restart (remote reception).

   replacing xxxx with the acutal numbers

[download]

Be Appropriate && Follow Your Curiosity

In reply to Log parsing exercises for Perl beginner - reasonable? by mikeraz

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