sh, bash
cc cc: no input files cc rotated is cc again, but it is not very friendly if called so naked.
dh dh: cannot read debian/control: No such file or directory hd dh debhelper isn't very cooperative too, while hexdump just waits for input.
gs sg Ghostscript starts interactive mode, while switch group shows a usage message - a valid solution here, imho, too.
And here is the script to find candidates for such programs:
#!/bin/bash for name in /sbin/* /usr/sbin/* /bin/* /usr/bin/* do len=${#name} # len=3 => 1:2 0:1, 2:1 0:2 # len=4 => 1:3 0:1, 2:2 0:2, 3:1 0:3 for n in $(seq 1 $((len-1))) do init=${name:n:len-n} rest=${name:0:n} # echo $init$rest which /usr/bin/$init$rest 2>/dev/null >/dev/null && echo $name $init$rest $n done done If finds longer sequences too, like (arj, jar) or (luatex, texlua) which aren't valid after every shift, but only after some certain shifts, which I misread in the beginning, but there are few, so it is easy to filter them out by hand.
