Ruby: ext Directory Reference

Ruby 3.0.5p211 (2022-11-24 revision ba5cf0f7c52d4d35cc6a173c89eda98ceffa2dcf)

ext Directory Reference

## Directories
directory | bigdecimal
directory | cgi
directory | continuation
directory | coverage
directory | date
directory | dbm
directory | digest
directory | etc
directory | fcntl
directory | fiber
directory | fiddle
directory | gdbm
directory | io
directory | json
directory | monitor
directory | nkf
directory | objspace
directory | openssl
directory | pathname
directory | psych
directory | pty
directory | racc
directory | rbconfig
directory | readline
directory | ripper
directory | socket
directory | stringio
directory | strscan
directory | syslog
directory | win32
directory | win32ole
directory | zlib