Plist file syntax

Question

I apologize if this subject has been covered already. I am looking for help interpreting the .plist files. I am not a programmer - but trying to learn - so please be gentle with your answers:-)
I know those files are written in XML language, and although I understand some of the syntax, I am stumped. What book(s) would I need to get to learn about this?
Example:
<dict>
<key>prefs</key>
<data>
bWNwIAA4AAUSTWFpbiBBZG1pbmlzdHJhdG9yAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
How do I go about figuring out what this stuff actually means?
Please help direct me to where I might learn more.
And another question: why are there 2 hostconfig files in the /etc directory, one ending with a tilde (hostconfig~) has some different settings?
Thank you for the patience.
Dora

Answer 1

Property list (.plist) files can only store objects of type NSNumber, NSDictionary, NSArray, NSString, NSDate, and a "catch-all" NSData. (Note that while I've specified the Cocoa-classes for these items, their Core Foundation equivalents are also included). For objects that aren't numbers, strings, and dates, the property list APIs provide a generic "NSData" type which allows you to save virtually any type of preference, provided it knows how to write itself to an NSData/CFData stream of bytes.
So, the entry you specified is a key "prefs" whose value is an NSData/CFData object. (Data byte values are base-64 encoded between the data tags).
For more info, see XML Property Lists.
Hope this helps....
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