Oleh Derevenko wrote:
> This might be not the best group for the question but if `cp' is discussed why could be `tail' worse?
> With 6.4.x `tail' utility command line parameters have been changed the way that compatibility with `tail' from 6.3.x 
has been broken. As the result the scripts that used `tail' need to be corrected during migration from 6.3.x to 6.4.x. 
On the other hand the parameters of `head' remained the same.
> Does it not look strange to anybody?

Yes, tail was changed to follow POSIX (-c requires an option). There is 
an PR open for head.

Regards,

Ryan Mansfield