A short search with Google brings me to this page, which tells me that most Netscape strings start with something like Mozilla/x.xxx(, and after that first opening parens, there is not the word compatible. This could be checked for with the following crummy code :

sub header_NS {
  # Assume that nobody uses Netscape anymore
  my $result = undef;

  # Get user agent passed as the only parameter
  my $user_agent = shift;

  if ($user_agent =~ m#^Mozilla/\d+#i) {
    # We have a Mozilla/NetScape compatible browser
    if ($user_agent !~ /compatible/i) {
      # And it's not even just "compatible", it's the real,
      # CSS burning, X crashing hellspawn
      $result = 1;
    };
  };

  return $result;
};

[download]

The above code checks for any browser that claims to beo Mozilla, but also claims to be the real thing and not something compatible. But I think your idea of using User-Agent headers for this is flawed, as there are many instances where proxies change the user agent and there are also other browsers which have real problems with CSS support. I recommend you put a "This site without CSS" link into your script, which calls your script again with the parameter ?nocss=1 appended to the URL. This allows users with broken browsers to easily use your website even if your magic detection does not work because you didn't anticipate their specific browser.

In reply to Re: Identifying browsers by Corion
in thread Identifying browsers by Anonymous Monk

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