Cygwin is a software package that enables one to work in a UNIX-like environment under a Windows machine. It is fast, reliable and easy to install. It has most of the applications one uses on UNIX (gcc, X, xfig, latex, Perl, bash, ps tools, textutils,...) and most of it is covered by the GNU public license. Cygwin supports many flavors of Windows:XP, 2000, 98, etc. For more info on cygwin go toCygwin.com.

The goal of this page is to describe a way of installing cygwin on a portable storage device like a portable hard drive or a USB memory stick. The main use of such a setup, obviously, is that it enables you to carry a UNIX like system in your pocket everywhere you go and use any Windows machine (e.g. Windows pc's at your university library) with your own powerful cygwin/UNIX tools.

Choice of Portable device

• USB memory stick: A core cygwin installation doesn't need more than a couple of hundred MBs. Thus a 1 GB USB memory stick easily gives you the capacity you need to install cygwin. But, remember that USB memory sticks are slow (bearable with NTFS crawling with FAT32) if you install a big file system  on them.

• CDROM's. Because CDROMs are read-only, they are a poor choice of media to install cygwin. See the following posts at cygwin.com:
  • http://www.cygwin.com/ml/cygwin/2003-07/msg00026.html
  • http://www.cygwin.com/ml/cygwin/2003-05/msg00692.html
  • http://www.cygwin.com/ml/cygwin/2003-05/msg00705.html
  • http://www.cygwin.com/ml/cygwin/2003-05/msg00728.html
  
  
• Portable Hard drives : Portable Hard drives are great. If you are getting one, make sure you get one that receives power through the USB cable and from the computer.

Choice of Filesystem

Installation

• Go to cygwin.com and install cygwin on your portable storage device.  Let's designate your portable storage device with "E:\" and assume that you installed cygwin in "E:\cygwin".

  As is, this installation will work only when your portable storage device is connected to the computer on which you performed the installation. What follows is  what you need to do so that your cygwin can work with any host windows computer.

• Unless it is not there, create the directory "E:\cygwin\home". Then create the directory "E:\cygwin\home\username", where username is a user name that you pick. (e.g. your name). This will be your home directory: whenever you start an rxvt or an xterm it will start with this directory as the current directory.

• Copy profile to E:\cygwin\etc. Open it with an editor (e.g. notepad) and replace the phrase "username" (it occurs twice) with the user name you have chosen above.

• Download X.tab and put it in "E:\". Rename it "X.bat" [*]. This script assumes that you installed cygwin under "E:\cygwin" on your storage device. If you installed it in some other directory you will need to modify this script to reflect that ( X.bat figures out the drive label of the portable device [assumed to be E in this discussion] on its own. So you have to change X.bat only if cygwin is installed in some directory other than "cygwin" in the root directory of your portable storage device). X.bat inserts several keys into the windows registry. This is required for cygwin to work. It also saves any key values that it might alter. Finally it starts a copy of the X server and a terminal (assuming that  X and rxvt were installed in step 1).[**]

• Download uninstall.tab and put it in "E:\". Rename it to "uninstall.bat" [*]. Run this script once you are done using cygwin and quit all cygwin software. It restores any registry keys that might have been altered when running "X.bat".

If you are using a very old windows, replace

 for /f %%A in ('cd') do set WD=%%A

set WD=%1