af_archive(5)							File Formats Manual						     af_archive(5)

NAME

       af_archive -- format of archive files in the Attribute Filesystem

SYNOPSIS

       #include <atfs.h>
       #include <afsys.h>

DESCRIPTION

       AtFS  archive  files are used to store the data and attributes of non-busy ASOs.  Beside these, some attributes (including all user defined
       attributes) of busy ASOs are stored in AtFS archive files.

       AtFS maintains two archive files for each line of development, one to hold the standard- and the user defined attributes and the  other	to
       hold the data and change notes.	These files are stored either in a subdirectory named AtFS or in a explicitly named directory somewhere in
       your file system.  The two archive files are named
	    Attr/<filename>	     (attributes) and
	    Data/<filename>	     (data).

       This manual contains a short, exemplary description of the archive structure.  All data in AtFS-archives are stored as ASCII-strings.   The
       archives contain keywords and keyletters. These are set in boldface in the following description.  Strings of the form <field> describe the
       purpose of the appropriate field in the archive.

       Here's the structure (the attributes file first):

								     The Header, ...

       ^BARHD	<archive_format_version>   <no_of_revisions>   <size_of_data>

								     ... the name ..

       ^BI   <hostname>   <path>   <name>   <type>   <variant(unused)>

								  ... and the owner ..

       ^BO   <owner's_name>   <owner's_host>   <owner's_domain>

						... followed by some attributes for the busy version ...

       ^BP   <gen_>   <rev_of_physical_predecessor>
       ^BL   <locker's_name>   <locker's_host>	 <locker's_domain>   <date_of_last_lock_change>

						  ... and the revision list, that contains all standard
							  attributes for non-busy versions. ...

       ^BR   <generation>   <revision>	 <state>   <mode>   <variant(unused)>
	    ^BA   <author's_name>   <_host>   <_domain>   <locker's_name>   <_host>   <_domain>
	    ^BT   <date_of_last_modification>	<_last_access>	 <_last_status_change>	 ...
					...   <_saving>   <_locking>
	    ^BM   <kind_of_representation>   <size_of_file>   <size_of_delta>	...
		      ...   <gen_>   <rev_of_phys._successor>	<gen_>	 <rev_of_phys._predecessor>
       ^BR ...
       ^BR ...

					      ... Now follows the list of lists of user defined attributes
					  ("-2 -2" indicates the busy version; "@" stands for a null byte). ...

       ^BUSEG
       ^BU -2 -2
       machine=vax@data=fs@@
       ^BU   <gen>   <rev>
       name=value@@
       ^BU ...

       The structure of the datafile:

       Data are represented either by deltas or by complete data-chunks...

       ^BDATA	<archive_format_version>

       ^BN   <gen>   <rev>   <size_of_note>
       --- empty log message ---

       ^BD   <gen>   <rev>   <kind_of_representation>	<size_of_data>
       A typical delta looks like:
       @67723@@@@44@67756@^A14@some text@6635@ and so on.
       Deltas are indicated by a "1" at the "kind_of_representation" field.

       ^BN   <gen>   <rev>   <size_of_note>
       This is a log message

       ^BD   <gen>   <rev>   <kind_of_representation>	<size_of_data>
       A "0" at the "kind_of_representation" field indicates that this
       version is stored completely.

       ^BN ...

       ^BD ...

AUTHOR

       Andreas Lampen, Tech. Univ. Berlin (andy@cs.tu-berlin.de)

1.6.119 															     af_archive(5)