The Heirloom Development Tools provide yacc, lex, m4, make, and SCCS as portable derivatives of the utilities released by Sun as part of OpenSolaris. The OpenSolaris utilities were in turn derived from the original Unix versions, and are assumed be conforming implementations of the POSIX standard.
ded, the directory editor, allows you to navigate multiple file lists or a directory tree, viewing or changing file attributes rapidly. In addition to conventional file information, it operates on files' RCS or SCCS archives, making it useful for source control as well as system administration. It is curses-based.