1) "duplicate" implies that you can only specify two outputs,
"multiply" is a better word describing the functionality.
2) fix other wording in the manpage
3) fix usage()
4) reorder local variables
5) fix sizeof() style
6) we need argv later, don't increment argv and rather iterate
over argc.
7) Improve error messages, print the filename which the write
failed to instead of printing the buffer itself (how much
sense does that make, printing 1024 Bytes of garbage?).
Also, give the name of the function which failed.
It actually makes the binaries smaller, the code easier to read
(gems like "val == true", "val == false" are gone) and actually
predictable in the sense of that we actually know what we're
working with (one bitwise operator was quite adventurous and
should now be fixed).
This is also more consistent with the other suckless projects
around which don't use boolean types.
