Developer(s)Bell Labs[citation needed]
Full nameBoot File System
Introducedwith UNIX System V
Partition IDs0x63 (MBR)
Directory contentssingle inode table
File allocation16-bit inodes
Max filename length14 characters
operating systems
SVR4, UnixWare[citation needed]

The Boot File System (named BFS on Linux, but BFS also refers to the Be File System) was used on UnixWare to store files necessary to its boot process.[1]

It does not support directories, and only allows contiguous allocation for files, to make it simpler to be used by the boot loader.


Besides the UnixWare support, Martin Hinner wrote a bfs kernel module for Linux that supports it.[2]

He documented the file system layout as part of the process.[3]

The Linux kernel implementation of BFS was written by Tigran Aivazian and it became part of the standard kernel sources on 28 October 1999 (Linux version 2.3.25).[4]

The original BFS was written at AT&T Bell Laboratories for the UNIX System V, Version 4.0 porting base in 1986.[citation needed] It was written by Ron Schnell, who is also the author of Dunnet (game).[citation needed]

BFS was the first non-S5[clarification needed] (System V) Filesystem written using VFS (Virtual Filesystem) for AT&T UNIX.


  1. ^ "UnixWare architecture supports multiplatform interoperability". InfoWorld: 66. 28 June 1993.
  2. ^ Martin Hinner (1999). "UnixWare boot filesystem for Linux". Martin Hinner. Retrieved 2008-12-21.
  3. ^ Martin Hinner (1999). "The BFS filesystem structure". Martin Hinner. Retrieved 2008-12-21.
  4. ^ Tigran Aivazian (1999). "Linux Implementation of SCO UnixWare BFS". Tigran Aivazian. Retrieved 2018-06-14.