Modifications to Cygwin on the CD

The CD contains an install of Cygwin that has been modified. Modifications were made for three purposes: make Cygwin runnable from a CD, make the CD appear as an application that runs an X server, to provide an ssh client with X forwarding, and to provide easy access to data. Cygwin is designed to be installed on a system rather than to be run from a CD. The method of making Cygwin run from the CD was taken from a post to the Cygwin mailing list on 19 July 2003. Below the post will be referred to as the "mailing list post". A few deviations from the methods of the mailing list post have been taken. The goal of the deviations has been to give the CD the appearance of being a single application that is an X Windows server that provides xterms. The user starts X by inserting the CD, gets one xterm, can create more xterms, can copy and paste text between xterms and native windows, and eventually exits the application. Cygwin offers much more than that, but that is how the CD has been designed. To facilitate X forwarding the openssh client has been configured to request X forwarding by default. To provide easy access to data, the user home directory is the current desktop rather than an unwritable directory on the CD.

Cygwin packages

The Cygwin install is from 16 November 2004. All default packages were installed plus the following:

• Archive
• sharutils
• unzip
• zip
• Editors
• nano
• nedit
• vim
• Interpreters
• perl
• Libraries
• regex
• Network
• openssh
• openssl
• Shells
• tcsh
• pdksh
• Utilities
• cygutils
• file
• bzip2
• X server
• xorg-x11-base - and all the packages that come with it
• xorg-x11-f100 fonts

Subtractions

• /cygwin.bat - not appropriate for running off of CD. Removed as recommended by the mailing list post
• /etc/passwd - not appropriate for running off of CD. Removed as recommended by the mailing list post
• /etc/group - not appropriate for running off of CD. Removed as recommended by the mailing list post
• /etc/profile - not appropriate for running off of CD. Removed as recommended by the mailing list post

Additions

• /run.bat
• A wizard script that launches when the CD is inserted into Windows XP/2000/NT computers.
• Win 98 users can double-click to launch the wizard.
• /X.bat
• Startup script that launches X Windows.
• The script exits when the X server exits.
• Modified from cygmin.bat that was provided by the mailing list post.
• Using commands from cygmin.bat, this script saves mount points when it starts and then restores them when it exits.
• Rather than running a bash shell, the script runs the X windows server.
• Before exiting, removes .* files and directories from the user's home directory (the desktop).
• /cygmin.ini
• Sets environment variables for bash shells.
• Modified from the mailing list post to set man path, include X binaries on path, use the desk top as the home directory, and set the prompt.
• Used by /X.bat and /usr/local/bin/runxwin.sh.
• /usr/local/bin/cleanhome.sh
• A bash script for cleaning home directory.
• Deletes .* unless .xlivecd_hide is present.
• If .xlive_hide is present sets Windows hide attribute for .* files and directories.
• Appropriate because the user's home directory is the desktop, and the desktop should not be cluttered by .bash_history and .ssh. Also, the CD should leave as few footprints as possible.
• Run by /X.bat.
• /usr/local/bin/runxwin.sh
• Modified version of /usr/X11R6/bin/startxwin.sh.
• Run by /X.bat.
• Places a shortcut on the desktop for running new xterms.
• Runs xwinclip to provide cross-platform cut and paste
• Does not exit until the X server exits.
• On exit shuts down xwinclip.
• On exit removes the xterm shortcut from the desktop.
• Name changed from startxwin.sh because it is likely to be on the path before the real McCoy.
• /index.html, /livecd/doc/*.html - Documentation.
• /AUTORUN.INF - Runs run.bat.
• /livecd/WizApp - The Wizard's Apprentice http://wizapp.sourceforge.net. Run by /run.bat.
• /livecd/install - contains tarball and script for installing Cygwin packages from the CD that will run very much the CD version.

Modifications.

• Drastically reduced set of terminfo entries.
• Cygwin terminal entry retained.
• Xterm terminal entry taken from X.org xterm package.
• User's home directories are their desktops.
• This change was made to provide users with convenient access to their data. It is assumed that users will want to transfer data to and from remote machines. Why make them navigate out of a Siberian home directory on the CD that isn't writable?
• Home directories are set in /cygmin.ini.
• /etc/ssh_config
• X11 forwarding is requested by default so that users need not use -X with ssh.
• Trusted X11 forwarding is requested by default so that users need not use -Y with ssh.

Documentation copyright and license

Copyright (C) 2004 by The Trustees of Indiana University. This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/). Distribution of substantively modified versions of this document is prohibited without the explicit permission of the copyright holder.