Program sfpwdchain2 | Chain of PWDs 
[SYNOPSIS]
sfpwdchain2 < inp.rsf sig=sig.rsf > out.rsf drift=n
[PARAMETERS]
bool    | drift | =n |  [y/n] | 	if shift filter 
file    | sig | = |   | 	auxiliary input file name
[DIRECTORY]
user/pwd
