It matches newlines at the end of the domain name :-

  print could_be_a_host("www.domain.com\n"); # says 1

[download]
\z instead of $ in the regexps would fix it for recent perls as would a judicously placed chomp - but I'm sure you know this already!

In reply to RE: Test the syntactic validity of a domain name by ncw
in thread Test the syntactic validity of a domain name by merlyn

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