updated doc with apple reference

format/bookmark/bookmark.md

@@ -1,4 +1,4 @@
-## Apple bookmarkData format
+## Apple `bookmarkData` format
 
 Apple's `bookmarkData` format is used to encode information that can be resolved
 into a `URL` object for a file even if the user moves or renames it. Can also
@@ -15,12 +15,17 @@ Property Lists. Notable examples include:
 - `com.apple.LSSharedFileList.RecentApplications.sfl2` - `sfl2` files are
   actually `plist` files of the `NSKeyedArchiver` format. They can be parsed the
   same as `plist` files, but they have a more complicated tree-like structure
-  than would typically be found. For more information about these types of files,
-  see [Sarah Edwards'](https://www.mac4n6.com/blog/2016/1/1/manual-analysis-of-nskeyedarchiver-formatted-plist-files-a-review-of-the-new-os-x-1011-recent-items)
+  than would typically be found, which can make locating and retrieving specific
+  values difficult, even once it has been converted to a JSON representation.
+  For more information about these types of files, see 
+  [Sarah Edwards'](https://www.mac4n6.com/blog/2016/1/1/manual-analysis-of-nskeyedarchiver-formatted-plist-files-a-review-of-the-new-os-x-1011-recent-items)
   excellent research on the subject.
 
-Locating `bookmarkData` objects in `NSKeyedArchiver` plist files is a place
-where `fq`'s recursive searching really shines:
+Locating `bookmarkData` objects in plist files, especially those of the
+`NSKeyedArchiver` type, is a place where `fq`'s recursive searching really
+shines. Here, we recursively descend through the decoded tree, probing for and 
+selecting any `bookmark` blobs, then converting them to readable JSON with
+`torepr`:
 ```
 fq '.. | select(format=="bookmark") | .map(. | torepr)' com.apple.LSSharedFileList.RecentApplications.sfl2
 ```
@@ -30,6 +35,7 @@ fq '.. | select(format=="bookmark") | .map(. | torepr)' com.apple.LSSharedFileLi
 [@dgmcdona](https://github.com/dgmcdona)
 
 ### References
+- https://developer.apple.com/documentation/foundation/url/2143023-bookmarkdata
 - https://mac-alias.readthedocs.io/en/latest/bookmark_fmt.html
 - https://www.mac4n6.com/blog/2016/1/1/manual-analysis-of-nskeyedarchiver-formatted-plist-files-a-review-of-the-new-os-x-1011-recent-items
 - https://michaellynn.github.io/2015/10/24/apples-bookmarkdata-exposed/