for removing the last n characters from a line that makes no use of sed OR awk:
> echo lkj | rev | cut -c (n+1)- | rev
so for example you can delete the last character one character using this:
> echo lkj | rev | cut -c 2- | rev
> lk
from rev manpage:
DESCRIPTION
The rev utility copies the specified files to the standard output, reversing the order of characters in every line. If no files are speci- fied, the standard input is read.