shithub: 9ferno

ref: 6966e8d72ae8fb72ebf98909acbd464aff84a3cc
dir: /man/3/tinyfs/

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tinyfs \- file system for miniscule devices
bind -c #F\fIname\fP /nvfs
.I 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
.B #F
device name is the
.I name
of a file in
.B /dev
on which the tiny file system will live.
For instance,
.B #Fnvram
refers to
.BR /dev/nvram .
The device must allow seek and write.
During the
.IR 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 formatted as an empty tiny file system.
.TF /nvfs
.B /nvfs
conventional mount point used by
.IR init (8)
.B /os/port/devtinyfs.c