perl regexes _may_ be able to handle this, but the code would be scaaaary

I felt like doing something scary. *grin* The trick is to use sexeger - a regex that operates on the reversed string.

s/{BS}/\b/g;
$_ = reverse $_;
my $k = 0;
s/(\010+)(??{ $k += length $+; "([^\010]{0,$k})" })(?{ $k -= length $+
+ })//g;
$_ = reverse $_;
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Don't forget to tune in for the next issue of H.R. Giger meets Perl. *grin*

Makeshifts last the longest.