Download the compressed tarball from
http://prdownloads.sourceforge.net/rdesktop/rdesktop-1.1.0.tar.gz
Uncompress the downloaded file by typing "tar -xzvf rdesktop-1.1.0.tar.gz" (no quotes).
After extraction, change in to the newly extracted directory by entering "cd rdesktop-1.1.0" (no quotes). Then, enter "./configure" (again, no quotes) to set up the installation.
Next, we'll compile the software. To acomplish this, enter "make" and press return - the compiler will spew it's usual gibberish at you - this is valuable to a programmer, but beyond the scope of this document. Only be worried if you see an error.
Okay, so it compiled - to install rdesktop on your system, type "make install" (no quotes - do you see a pattern?) and it'll do it's thing.
./rdesktop "server", where "server" is the terminal server's hostname or IP address. The software should open a client session with your Terminal Server.
Usage: ./rdesktop [options] server
-u: user name
-d: domain
-s: shell
-c: working directory
-p: password (autologin)
-n: client hostname
-k: keyboard layout (hex)
-g: desktop geometry (WxH)
-f: full-screen mode
-b: force bitmap updates
-e: disable encryption (French TS)
-m: do not sendmotion events
-l: do not request license