perlintern - autogenerated documentation of purely internal Perl functions
This file is the autogenerated documentation of functions in the Perl intrepreter that are documented using Perl's internal documentation format but are not marked as part of the Perl API. In other words, they are not for use in extensions!
The autodocumentation system was orignally added to the Perl core by Benjamin Stuhl. Documentation is by whoever was kind enough to document their functions.