The format is binary ill documented and proprietary - standard M$. You could use Win32::OLE to get at it via Explorer but given that the URLs are in plain text within these files you can just do something like this to extract them into a file:

 perl -ne "BEGIN{$/=' '}print qq!$1\n! if m!(http:[\w\.\-:/]+)!" index
+.dat > outfile.txt
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As it is a binary file we can't depend on the default "\n" input record separator. We use a single space as there are space chars around every URL so we get a single URL per chunk of input. Kinda like newlines but not.

I have IE6 on Win2k but I don't have any files on the system called MSHistNNNNN.. Eyeballing your files it looks like the last 8 digits are YYYYMMDD. It looks the same way IE displays it with individual files for the last 7 days then some sort of archive for 2 and 3 weeks ago.

HTH

It's an Explorer trick. Even with the options to view system files and hidden files, Explorer will not show you your own IE6 History in this format. If you look at the History folder of a user other than the currently logged in user, you'll see these "special" folders. You can also load up cmd.exe and cd "C:\Documents and Settings\username\Local Settings\History\History.IE5". It's really fricked up. Even cmd.exe gets confused with some things here. If you chdir up once to (Local Settings\History) and do a 'dir', it'll tell you file not found. Even though you can still cd to History.IE5. That's Microsoft for you.

Try a "dir /a" instead. The directory itself is marked as System.

My best guess is the format goes like this:

# $c_xxxx means 'current' year, month and date
# $l_xxxx means 'last' year, month and date
#    (of the previous history file)

"MSHist01" . $l_year . $l_month . $l_date .
   $c_year . $c_month . $c_date
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