what does & mean in this line of code ?

To Perl, it means "ignore the prototype". To some people, it seems to mean something else I don't know.

Why is variable $dir surrounded by () ?

my $dir = @_; would assign the number of elements in @_ to $dir.

What does [my (@dirs,$list);] do ?

A short way of writing 

my @dirs;
my $list;

[download]

Usually we declare list in bracket on right hand side and that contains values.

This makes no sense. For starters, you can't declare lists since they're not variables.

Where can I find more details about this code ?

my

A question of my own: Why do you add a space in front of every "?"?

In reply to Re: please explain some code by ikegami
in thread please explain some code by manishrathi

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