在网络安全中经常会遇到rootkit

				#!/usr/bin/perl								# List all files in a directory								my $viewdir = $ARGV[0];								if ($viewdir ne "")				  {				    opendir(DIR,$viewdir) || die "Can't open directory";				    @filenames = readdir(DIR);				    closedir(DIR);								    foreach $file (@filenames)				      {					if ($file ne "." && $file ne "..")					  {					    if(substr($file,0,1) eq ".")					      {					        print $viewdir,"/",$file,"\n";					      }					  }				      }				  }