Convert 4 (Man Page) to 9 (Man Page)

The 4 file extension refers to Unix Section 4 Manual Pages, which document special files and device drivers. These files, such as "mouse.4", describe how devices interact with the Unix operating system and are accessed using the "man" utility. Historically, these manual pages have been a fundamental part of Unix documentation, helping users understand and manage system devices.

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.