# grab the first two non-whitespace items, separated by whitespace.
my ($date, $time) = $s =~ /(\S+)\s+(\S+)/;

# grab the last two portions of the disk name, 
# which is immediately followed by the first ^ in the file.
my ($disk) = $s =~ /\\(\w+\\\w+)\^/;

# grab the user name, which is the string before the last ^,
# which in turn is followed by some white space and the end of the string.
# You can take out the \s+ if the space between the ^ and end of string was an artifact of your post.
my ($user) = $s =~ /(\w+)\^\s+$/;