according to the definition in perlre, \Z and $ should, under all flag settings, be matching everywhere that \z does, so the fact that one is getting matches with \z but not \Z or $, is at best, an undocumented violation of that contract.

Trying this out in my 5.10.1 debugger on (Debian)Linux, I'm getting quite erratic behavior: 

  DB<525> open $fh, '>', \$memory
  DB<526> print $fh 'abc';
  DB<527> x $memory =~ m/(.*)\Z/
  empty array
  DB<528> print $fh 'def';
  DB<529> x $memory =~ m/(.*)\Z/
0  'abcdef'
  DB<530> print $fh 'ghi';
  DB<531> x $memory =~ m/(.*)\Z/
  empty array
  DB<532> print $fh 'jkl';
  DB<533> x $memory =~ m/(.*)\Z/
  empty array
  DB<534> print $fh 'mno';
  DB<535> x $memory =~ m/(.*)\Z/
0  'abcdefghijklmno'
which just smells of buggity-bug-bug-bug.

In reply to Re: pattern match against in-memory file causes odd behavior by wrog
in thread pattern match against in-memory file causes odd behavior by kixix

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