Programming :: Get Webalizer To Analyse Some Log Files?

I'm trying to get webalizer to analyse some log files. The server uses virtual hosts and has log rotations on and also uses turbopanel (now known as simple control panel). Because of this, the documentation is limited and webalizer works in a weird way. I found this perl script under turbopanel called webalizerrun.pl the code is as follows:

Code:
#!/usr/bin/perl
$WEBALIZER = "/usr/bin/webalizer";
chomp($var = shift);
$wdir = "$var/conf/webalizer";
opendir(DIR, $wdir) or die "Unable to read $wdir: $!";

[Code]...

Here's what I want to do, and I believe I can do this using this code with slight modifications. As of now, the log files for each site is in the folder specified above with the file named as "domain-name_access_log" and then the log rotation just adds a number to the end of that. I want use this perl script to run webalizer for a particular site and have its output be placed in directory.

1.) Line 4: chomp($var = shift): I know chomp is used to remove trailing characters, but what character in this case? How may I find that out? Also what does $var = shift do inside chomp?

2.) Line 8: What exactly does the readdir function do? What does it return to $domain?

The rest seems similar to csh, checks if it's dir or file and then changes to the directory and runs webalizer on that directory.