Apple describes Safari's "Private Browsing" feature as follows:
When you browse the web, Safari stores information about the websites you visit including the content and any user names, passwords, and credit card numbers you enter. Other people who use your computer can view that information. If you don't want this information stored, use Private Browsing.... If you neglected to turn on Private Browsing before you browsed, choose Safari > Reset Safari.
dscacheutil -cachedump -entries Host
This will list all entries cached by Leopard (including the date and time of last access), even when Private Browsing is enabled. Even using Reset Safari will not clear these entries. To manually clear these entries, use the following command in Terminal:
dscacheutil -flushcache
The cache is also cleared once you log out of your Leopard account. While logged in, however, any other account on the system (even Guest users) can execute the above command to view sites you have visited.
Mac OS X Hints
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