Sorry, I misread. Looking for more information I saw the relevant commit message for why -b is used: revision 1.3 date: 2013-05-16 11:28:11 +0300; author: obache; state: Exp; lines: +2 -2; commitid: BmXjmoKqAa22CPPw; add `-b' (binary) option for SED to prevent special processing about CR+LF.