Convert OPML to 9 (Man Page)

OPML, or Outline Processor Markup Language, is a file format utilized primarily for outlining data structures. Initially developed in 2000 by UserLand Software, OPML was designed to facilitate the exchange of outline-based information between different software applications. Its uses have expanded over time, notably in organizing RSS feed lists and managing hierarchical data. The OPML file extension denotes XML-based documents that offer simplicity and interoperability in transferring structured information across diverse platforms. In essence, OPML serves as a versatile tool in the realm of data organization and syndication.

The 9 file extension refers to Section 9 of the Unix manual pages, specifically covering Kernel Routines. These manual pages provide detailed information on kernel APIs, internal structures, and other essential aspects of kernel development. Developed by Dennis Ritchie and Ken Thompson at AT&T Bell Laboratories in 1971, Section 9 is crucial for kernel developers but is not universally available due to its specialized nature.