Previously, I wrote about using Rtools when one already has Cygwin installed on a MS Windows machine. The "solution" was to avoid putting the Cygwin into the PATH variable and to create a new script which adds Rtools to the PATH variable on the fly. This (the first thing) eventually means that I was not able to use Unix tools (that are installed with Cygwin) in the MS Windows command terminal (prompt). For example, I was prepairing the presentation using the LaTeX Beamer package and I usually use a Makefile to ease the repeated compilation. In order to be able to use make and other unix shell tools, I created another startup script (CMD_Cygwin.bat) with the content as shown bellow.
rem --- Add Cygwin and current folder to the PATH ---
rem --- Start the Command Prompt ---