* doc/tar.texi (Extended File Attributes): The default extraction pattern consists of just 'user.*' namespace only. While on it, try to explain the reasons for this default behavior. --- doc/tar.texi | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/doc/tar.texi b/doc/tar.texi index 389a3448..e03ce3d4 100644 --- a/doc/tar.texi +++ b/doc/tar.texi @@ -5647,9 +5647,14 @@ Disable extended attributes support. This is the default. Attribute names are strings prefixed by a @dfn{namespace} name and a dot. Currently, four namespaces exist: @samp{user}, @samp{trusted}, @samp{security} and @samp{system}. By default, when @option{--xattr} -is used, all names are stored in the archive (or extracted, if using -@option{--extract}). This can be controlled using the following -options: +is used, all names are stored in the archive (with @option{--create}), +but only @samp{user} namespace is extracted (if using @option{--extract}). +The reason for this behavior is that any other, system defined attributes +don't provide us sufficient compatibility promise. Storing all attributes +is safe operation for the archiving purposes. Though extracting those +(often security related) attributes on a different system than originally +archived can lead to extraction failures, or even misinterpretations. +This behavior can be controlled using the following options: @table @option @item --xattrs-exclude=@var{pattern} @@ -5659,6 +5664,10 @@ Specify exclude pattern for extended attributes. Specify include pattern for extended attributes. @end table +Users shall manually check the attributes are binary compatible with the +target system first, before any other namespace is extracted with an +explicit @option{--xattr-include} option. + Here, the @var{pattern} is a globbing pattern. For example, the following command: -- 2.33.1