SSH1, SSH2, F-Secure SSH Server, and OpenSSH may all be tailored in
various ways by compile-time configuration with the
configure script. We've covered the
SSH-specific flags, but remember that other operating system-specific
flags may also apply to your installation, so be sure to read the
installation notes supplied with the software.
Once installed, SSH software may replace the insecure r-commands on
your Unix system, not only when run directly, but also within other
programs that invoke rsh, such as Emacs and Pine.