TINYFS(3) TINYFS(3)
NAME
tinyfs - file system for miniscule devices
SYNOPSIS
bind -c #Fname /nvfs
DESCRIPTION
Tinyfs provides file system access to the contents of low-
capacity devices, ranging from several hundred bytes (at
least 144 bytes) to at most the order of a kilobyte. It is
provided to support file system access to small non-volatile
memories, as for instance are found in some real-time clock
chips, where IDs, keys, PINs, certificates and the like
might be stored by either client or server.
The file system has only one directory, its root, which can
contain only files. Once created, a write can only append
to a file; random updates are not allowed, although the file
could be truncated and rewritten.
The device specifier following the #F device name is the
name of a file in /dev on which the tiny file system will
live. For instance, #Fnvram refers to /dev/nvram. The
device must allow seek and write. During the attach, the
system scans the device, checking the file system structure
by building a table of files, and checking a checksum stored
in each block; inconsistent structure is reinitialised, and
thus a previously unused device will emerge correctly for-
matted as an empty tiny file system.
FILES
/nvfs conventional mount point used by init(8)
SOURCE
/os/port/devtinyfs.c
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