New -xattr mode "any" to process all xattr namespaces of local filesystem

xorriso/xorriso.texi

@@ -50,7 +50,7 @@
 @c man .\" First parameter, NAME, should be all caps
 @c man .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 @c man .\" other parameters are allowed: see man(7), man(1)
-@c man .TH XORRISO 1 "Version 1.4.9, Sep 16, 2017"
+@c man .TH XORRISO 1 "Version 1.4.9, Oct 10, 2017"
 @c man .\" Please adjust this date whenever revising the manpage.
 @c man .\"
 @c man .\" Some roff macros, for reference:
@@ -613,9 +613,15 @@ only on GNU/Linux and FreeBSD.
 @cindex extattr, _definition
 @strong{xattr} (aka EA, or extattr)
 are pairs of name and value which can be attached to file objects. AAIP is
-able to represent them and @command{xorriso} can record and restore pairs which
-have names out of the user namespace. I.e. those which begin with "user.",
-like "user.x" or "user.whatever". Name has to be a 0 terminated string.
+able to represent them and @command{xorriso} can record and restore them.
+@*
+But be aware that pairs with names of non-user namespaces are not necessarily
+portable between operating systems and not even between filesystems.
+I.e. only those which begin with "user.", like "user.x" or "user.whatever",
+can unconditionally be expected to be appropriate on other machines and disks.
+Processing of other xattr may need administrator privileges. 
+@*
+Name has to be a 0 terminated string.
 Value may be any array of bytes which does not exceed the size of 4095 bytes.
 xattr processing happens only if it is enabled by command
 @strong{-xattr}.
@@ -1172,12 +1178,20 @@ load AAIP data from ISO images, test ACL during file comparison,
 and restore ACLs to disk files when extracting them from ISO images.
 See also commands -getfacl, -setfacl.
 @c man .TP
-@item -xattr "on"|"off"
+@item -xattr "on"|"user"|"any"|"off"
 @kindex -xattr   controls handling of xattr (EA)
 @cindex xattr, control handling, -xattr
-Enable or disable processing of xattr attributes in user namespace.
+Enable or disable processing of xattr attributes.
 If enabled, then @command{xorriso} will handle xattr similar to ACL.
 See also commands -getfattr, -setfattr and above paragraph about xattr.
+@*
+Modes "on" and "user" read and write only attributes from namespace "user".
+@*
+Mode "any" processes attributes of all namespaces. This might need adminstrator
+privileges, even if the owner of the disk file tries to read or write the
+attributes.
+@*
+Note that xattr from namespace "isofs." are never restored to disk.
 @c man .TP
 @item -md5 "on"|"all"|"off"|"load_check_off"
 @kindex -md5   controls handling of MD5 sums
@@ -1218,8 +1232,19 @@ actions get_md5, check_md5, and via -check_media.
 @kindex -for_backup    -acl,-xattr,-hardlinks,-md5
 @cindex Backup, enable features, -for_backup
 Enable all extra features which help to produce or to restore backups with
-highest fidelity of file properties.
-Currently this is a shortcut for: -hardlinks on -acl on -xattr on -md5 on.
+highest fidelity of file properties. Currently this is a shortcut for:
+@*
+-hardlinks on -acl on -xattr any -md5 on
+@*
+If you restore a backup with xattr from non-user namespaces, then make sure
+that the target operating system and filesystem know what these attributes
+mean. Possibly you will need administrator privileges to record or restore
+such attributes. At recording time, xorriso will try to tolerate missing
+privileges and just record what is readable.
+But at restore time, missing privileges will cause failure events.
+@*
+Command -xattr "user" after command -for_backup excludes non-user attributes
+from being recorded or restored.
 @c man .TP
 @item -ecma119_map "stripped"|"unmapped"|"lowercase"|"uppercase"
 @kindex -ecma119_map    names w/o Rock Ridge, Joliet