Arguments will be in the array @ARGV. For example:

our($arg1,$op,$arg2) = @ARGV;
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would read the first three arguments from the command-line into $arg1, $op, and $arg2. For more advanced command-line processing, you can use Getopt::Std or Getopt::Long.

As duff said, certain characters will be interpreted by the shell and need to be escaped or avoided.