documentation

• perltie#Tying FileHandles
• perlfunc#tie
• perlfunc#tied

example CPAN modules

• Tie::Handle — Perl core since v5.004_05
• Tie::StdHandle — Perl core since v5.8.9, @ISA = 'Tie::Handle';
• Tie::Handle::Base — attached to File::Replace
• CGI::Capture::TieSTDIN — attached to CGI::Capture
• Tie::Handle::Scalar
• Tie::Handle::Filter ⇒ Text::OutputFilter
• IO-Stringy's — IO::Lines, IO::Scalar, IO::ScalarArray, etc

see also

• PerlIO::scalar
• perlipc §Bidirectional Communication with Yourself
• perl58delta says "File handles can be opened to "in memory" files held in Perl scalars via:"
  • open($fh,'>', \$variable) || ...