For installation instructions see the Section called Installing Ed-0.2 in Chapter 6.
Ed (0.2):
ftp://ftp.gnu.org/gnu/ed/
Ed Mkstemp Patch:
http://www.linuxfromscratch.org/patches/lfs/5.0/ed-0.2-mkstemp.patch
GNU ed is an 8-bit clean, POSIX-compliant line editor.
Installed programs: ed and red (link to ed)
ed is a line-oriented text editor. It can be used to create, display, modify and otherwise manipulate text files.
red is a restricted ed -- it can only edit files in the current directory and cannot execute shell commands.
Ed depends on: Bash, Binutils, Coreutils, Diffutils, GCC, Glibc, Grep, Make, Sed.