setting tab stops

[Tom Reingold]

This question is not relevant to C, but I saw a nice algorithm, and I
think I saw it in comp.lang.c.  Someone posted a very terse way of
calculating how many spaces to move given an input of tabs.  I think it
used the modulo operator and some bitwise operators.  It was far too
terse and elegant for me to think of.  Can someone express what I am
thinking of?  The assumption is that the terminal tabs at every eighth
position.
--
                                        Tom Reingold
                                        tr at samadams.princeton.edu
                                        rutgers!princeton!samadams!tr
                                        201-577-5814
                                        "Brew strength depends upon the
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