in reply to hash referencing...best approach?

sub make_session {
   my ($u,$a,$s)=@_;
   %session_hash={
       user=>$u,
       dept=>$a
   };
       $s=\%session_hash;
}

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You've muddled several things, here. The hash should be assigned with a list, not a block. There's no reason to create $s, since you're just throwing it away. You can return the reference by just saying 
      \%session_hash;

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as the last line. You don't say where the result of make_session goes, and you don't declare %session_hash as a lexical in the sub, which means you're going to be returning a reference to the same thing every time. 

   while (my $line2=<HTTP>) {
       chomp;

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I'm guessing that here you want to chomp $line2.

I think I know what you want to do, but I'm not sure: Create a hash entry for each unique session, and associate a filename with it. Then, when you're reading the log files, you'll parse out the session name, and write (append) the line onto the associated file. Is that right?

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Re: Re: hash referencing...best approach?
by Anonymous Monk on Nov 24, 2003 at 21:32 UTC
    "I think I know what you want to do, but I'm not sure: Create a hash entry for each unique session, and associate a filename with it. Then, when you're reading the log files, you'll parse out the session name, and write (append) the line onto the associated file. Is that right? "

    This assesement is pretty accurate. What I want to have at the end of processing is a series of dept. specific access files:

    tools_access.log
    help_access.log
    ...

    Even better would be the full line from the access log file with the user_code and dept_code added to the end of it so we could not only track dept ussage but user usage within each dept.

    I don't know if that was any clearer or not...
[reply]
      Ok, let's see if this gets you started. I'm going to write this as mostly pseudocode comments. You get to fill in the code. 
      my %session_hash;
my %departments;
# for each of the 6 session files,
#     open and read line-by-line
#         parse out user_id, session_id, dept_code
          $session_hash{$session_id} = $dept_code;
          $departments{$dept_code}++;
#
# for each apache log
#     open and read line-by-line
#         parse out session_id
#         append the line to the file associated with $session_hash{$s
+ession_id}

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      If you have a relatively small number of departments (keys %departments), you can keep all the output files open for writing. Otherwise, you'll need to open for append each time you want to write a line of output. (You could also hold some number of lines in memory and write them out every so often, for a little less open and closing action.)

      HTH.

      The PerlMonk tr/// Advocate
[reply]
[d/l]
        I have about 40 possible departments, so I just wrote a small sub routine 

        sub write_it{
my ($dept,$output)=@_;
my $output_file=$dept."_access.log";
open DATA,">> $output_file")||die ("unable to open $output_file $!\n")
+;
print DATA $output."\n";
close DATA;

}

        [download]


        This works pretty great, I was able to read through one of the access logs and create the specific files in about 4 minutes. The one problem I have now is appending the user_code to the end of the access log line.

        I tried to change the way I 'write' to the session_hash while reading the session logs to : 
        $session_hash($sessio_id}{$user}=$dept_code;

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        But this just screwed me up later down the line when I reading through the access logs. For this part I currently have: 
            open (HTTP,$access_log)||die ("unable to open $access_log $!\n");
    while (my $line2=<HTTP>) {
        chomp $line2;
        my @fields=split /\s+/, $line2;
        my $session=@fields[6];
            my $session=substr($session,(index($session,"?")+12),(inde
+x($session,"|"))-(index($session,"?")+12) );
            if (length($session) ==52) {
                &write_it($session_hash{$session},$line2);
            }

        [download]
        I tried to incorporate the user_code part into this and ended up getting the hash address everywhere. In other words, my file names became hash addresses and my user_code values where null. Surely I am missing something minor here. Thanks for all the help thus far, it has proven most superb.
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