-*- Text -*-

Unfortunatly, there is not much in the way of documentation yet.  The
technical aspects of XDFS and Xdelta are described in the paper in
this directory "xdfs.ps.gz".  This paper also describes the high level
design of the XDFS application-level file system.  The best you can do
now is read the code for the examples in the "test" directory and the
header file "xdfs.h".

The "xdelta2" application installed by this package has this synopsis:

usage: xdelta2 COMMAND [OPTIONS] [ARG1 ...]
COMMAND is one of:
  create   XDFS_LOC
  register XDFS_LOC ARCHIVE_NAME
  insert   XDFS_LOC ARCHIVE_NAME VERSION_FILE
  retrieve XDFS_LOC ARCHIVE_NAME VERSION_NUMBER OUTPUT_FILE
  list     XDFS_LOC ARCHIVE_NAME
  stat     XDFS_LOC ARCHIVE_NAME
  show     XDFS_LOC
OPTIONS are:
  -v, --version
  -h, --help
  -M, --md5
  -S, --sha
All commands operate on an XDFS_LOC, a directory containing a single
XDFS volume.  An XDFS volume contains any number of archives, given
by their ARCHIVE_NAME.
The CREATE command creates a volume, and the REGISTER command creates
an archive within that volume.  Optionally, the REGISTER command may
be accompanied by --md5 or --sha, causing XDFS to index versions by the
MD5 or SHA-1 message digest function.
The INSERT and RETRIEVE commands correspond to RCS ci and co
The LIST command lists versions in an archive (optionally, the message
digest value).
The SHOW command lists all the archives in a volume.

Here is a transcript that demonstrates how to use the application:

$ ./xdelta2 create V
$ ./xdelta2 register --md5 V xdfsapp.c
$ ./xdelta2 show V
xdfsapp.c
$ ./xdelta2 insert V xdfsapp.c ./xdfsapp.c
$ #[insert a newline]
$ ./xdelta2 insert V xdfsapp.c ./xdfsapp.c
$ ./xdelta2 list V xdfsapp.c
Version  Length  MD5
      1   12394  0a916737740b8c06683e7f071ee9e427
      2   12395  271508e1496749179f6fdc2c946f2afb
$ ./xdelta2 stat V xdfsapp.c
XDFS stats for file:         /xdfsapp.c
Compression policy:          Forward
Flags:                       MD5 Digest
Version count:               2
Unique Version count:        2
Average file size:           12394
Unencoded size:              24789
Encoded size:                12420
Literal size:                12394
Control size:                26
Patch size:                  0
Ideal compression:           0.501
Patch files:                 0
Literal files:               1
Current cluster versions:    2
$ ./xdelta2 retrieve V xdfsapp.c 1 ./xdfsapp.c.1
$ ./xdelta2 retrieve V xdfsapp.c 2 ./xdfsapp.c.2
$ cmp xdfsapp.c.2 xdfsapp.c
$ diff xdfsapp.c.1 xdfsapp.c
133a134
>
$
