Please support hex codes in sed. Example: echo "foobarbazblargblurg" | sed 's/./&\x44/g' It should output: fDoDoDbDaDrDbDaDzDbDlDaDrDgDbDlDuDrDgD Instead it output: fx44ox44ox44bx44ax44rx44bx44ax44zx44bx44lx44ax44rx44gx44bx44lx44ux44rx44gx44