765 lines
46 KiB
Plaintext
765 lines
46 KiB
Plaintext
Secure CVS Pserver Mini-HOWTO
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Morgon Kanter
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<morgon AT surgo DOT net>
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Copyright © 2003 Morgon Kanter
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February 2003
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Revision History
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Revision 1.1 2003-03-21 Revised by: mk
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Fixed a missing link and added a section on CVSGrab
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Revision 1.0 2003-02-01 Revised by: mk
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Initial Release, reviewed by LDP.
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This document will help you set up a more secure CVS Pserver for anonymous
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CVS access.
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Permission is granted to copy, distribute, and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.2 or any
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later version published by the Free Software Foundation; with no Invariant
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Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the
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license is included in Section 6, entitled "GNU Free Documentation License".
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-----------------------------------------------------------------------------
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Table of Contents
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1. Introduction
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2. Getting the tools
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2.1. What you need
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2.2. Compiling the tools
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3. Setting up the tools
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3.1. Creating the CVS Repository
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3.2. Setting up the jail
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3.3. Adding anonymous access
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3.4. Not quite done yet! Changing lock file locations
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4. Alternatives to the Pserver
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4.1. Access for developers
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4.2. Anonymous CVS access by http
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4.3. CVSGrab
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5. Acknowledgements
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6. GNU Free Documentation License
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1. Introduction
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CVS Pserver is, by definition, an insecure protocol. Among other things,
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passwords are transmitted in plain text, making it undesirable for much use.
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However, CVS Pserver is very good for providing anonymous CVS access to a
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repository.
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In this document we will introduce you to setting up a CVS repository
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(although not intruding on the CVS HOWTO's space), and how to set up a chroot
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jail for the Pserver. We will also talk about using SSH for developer access
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to a repository.
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-----------------------------------------------------------------------------
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2. Getting the tools
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2.1. What you need
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You'll need the following things in order to set up a secure Pserver:
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CVS
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Of course, you will need to have CVS in order to be running it. You can
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get it [http://www.cvshome.org] here.
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cvsd
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cvsd is a program that will run the CVS Pserver in a chroot jail. You
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can get it [http://tiefighter.et.tudelft.nl/~arthur/cvsd/] here.
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SSHd
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If you want your developers to have secure access to the repository,
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you'll have to be running an SSH server. However, setting up that access
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is beyond the scope of this Mini-HOWTO. More information can be found at
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[http://www.tldp.org/HOWTO/CVS-RCS-HOWTO.html] the CVS-RCS howto.
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-----------------------------------------------------------------------------
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2.2. Compiling the tools
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If you are compiling from the sources, follow these instructions. If you
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downloaded binaries, skip ahead to Section 2.2.2.
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-----------------------------------------------------------------------------
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2.2.1. Compiling CVS
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After you have downloaded the CVS sources, unpack them into a directory and
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cd into it. The default prefix is /usr/local; we've changed it to /usr for
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this example. You might want to change mandir to wherever your man pages
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reside (the default is PREFIX/man).
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$ ./configure --prefix=/usr
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$ make
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# make install
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-----------------------------------------------------------------------------
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2.2.2. Compiling cvsd
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There are a few configure switches you should be aware of here. The default
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prefix is /usr/local, which in this document we are changing to /usr. You
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should also change sysconfdir to /etc, where the system config files usually
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reside. You might want to change mandir to wherever your manual pages reside
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as well.
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$ ./configure --prefix=/usr --sysconfdir=/etc
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$ make
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# make install
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Now lets go on to setting up these wonderful tools.
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-----------------------------------------------------------------------------
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3. Setting up the tools
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Now that CVS and cvsd are built, let's set them up.
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-----------------------------------------------------------------------------
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3.1. Creating the CVS Repository
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Before we begin, I strongly recommend you read the CVS manual that was
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installed with the rest of CVS. If the stand-alone info browser or the
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texinfo package is installed on your system, you can see this manual by
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typing the command info cvs at your shell.
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First, plan out where you want your repository. Debian defaults to /var/lib
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/cvs. My repository is under the directory /cvs/root, and is on its own small
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partition. What you do depends on your needs and can vary widely.
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Important Make sure that the repository is a subdirectory of an empty
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directory! For example, if you are installing it into /var/lib/cvs,
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put the repository in /var/lib/cvs/root (or whatever you want for
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the last directory). This is because we create a chroot jail for
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the Pserver!
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After you have planned where you want to put your repository, made the
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necessary partitions, if desired, and run the following command (we assume
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that it will be at /cvs/root):
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$ cvs -d /cvs/root init
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That will initialize your repository and set up the necessary CVSROOT
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files.
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-----------------------------------------------------------------------------
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3.2. Setting up the jail
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Now that we have the CVSROOT set up, we need to copy the appropriate
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libraries and files for cvsd, which runs the Pserver in the chroot jail.
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-----------------------------------------------------------------------------
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3.2.1. Transferring the necessary files
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Note If you installed cvsd from a package management system like RPM, this
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may already be done for you. If that is the case, skip ahead to the next
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step.
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Change your directory to /cvs (or whatever the directory before your root is)
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and enter the following commands:
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$ cvsd-buildroot /cvs
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$ mkdir -p var/lock
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$ adduser cvsd
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$ addgroup cvsd
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Thankfully, cvsd comes with the script cvsd-buildroot, so we don't have to
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do all the necessary copying by hand. However, you should edit the /cvs/etc/
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passwd file, and remove the entry for "root," as it's unneeded.
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-----------------------------------------------------------------------------
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3.2.2. Configuring cvsd
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The defaults in /etc/cvsd/cvsd.conf are okay, but can be less than
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desirable. Make sure that RootJail is set to wherever the chroot jail you
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built is, and the repository is the directory where the repository is
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relative to the chroot jail. Set maxconnections to whatever you desire, and
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make sure that Uid and Gid are set to cvsd. If you are lacking an
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already-built cvsd.conf file, here is mine:
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Example 1. My cvsd.conf
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Uid cvsd
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Gid cvsd
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PidFile /var/run/cvsd.pid
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RootJail /cvs
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MaxConnections 10
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Nice 1
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Listen * 2401
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Repos /root
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Limit coredumpsize 0
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-----------------------------------------------------------------------------
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3.3. Adding anonymous access
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It's back to configuring CVS, but don't worry, we are almost there! We have
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to edit a couple of necessary files to allow for anonymous access. First,
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making sure you aren't in the CVS directory, check out the CVSROOT module:
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# cvs -d /cvs/root checkout CVSROOT
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# cd CVSROOT
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Now edit the file READERS. Create it if it isn't there, and add a line that
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reads "anonymous".
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Important You NEED to have an extra line at the end of the file!
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The file READERS is a list of users who have read-only access to the CVS
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repository. People with write access are listed in the file WRITERS. Read the
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cvs manual [1] for more information on these files.
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Now commit the repository with the command below. We assume that your
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current working directory is CVSROOT. If it isn't, forget the cd step.
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# cd ../
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# cvs -d /cvs/root commit
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You should now get a message that says something like Re-building
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administrative files, which means that it was successful.
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One last step and we're all done! Run the following command, and when
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prompted for a password, just press ENTER:
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# cvsd-passwd /cvs/root anonymous
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Congratulations! You now have secure, anonymous CVS Pserver access to the
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repository!
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-----------------------------------------------------------------------------
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3.4. Not quite done yet! Changing lock file locations
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There is one small feature here that is really beyond the scope of this
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Mini-HOWTO but is worth noting nonetheless. It is the ability to change the
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directory where the Pserver will place lock files.
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Normally the Pserver will place lock files in the same directory as the
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files that you are trying to check out, but this can cause permissions
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mayhem. Step back to when we built the chroot jail for cvsd; we also created
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the directory var/lock. This is where we will place the lockfiles instead.
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So use the following example, replacing /cvs with wherever your chroot
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environment is, and var with wherever the locks are going to be placed. Mine
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are placed in var/lock, and there is nothing else under var, so a chown -R is
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safe. Also, replace the cvsd user and group ids with the user and group ids
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that cvsd runs as.
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# cd /cvs
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# chown -R cvsd:cvsd var
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# chmod -R 775 var
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# cd
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# cvs -d /cvs/root checkout CVSROOT
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# cd CVSROOT
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Now we want to edit the file config. Change lock dir to the directory you
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want the locks to be placed, in our case /var/lock.
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Important Note that this applies to the Pserver AS WELL AS THE NON-CHROOT SSH
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LOGIN METHOD! Ensure that this directory is not only in existence,
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but that you can write to it as well, relative to your root
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directory. This is why I have chosen /var/lock, because it
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satisfies those conditions.
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Now commit the changes:
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# cd ../
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# cvs -d /cvs/root commit
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And that's it!
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-----------------------------------------------------------------------------
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4. Alternatives to the Pserver
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4.1. Access for developers
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Pserver is not a very good method to implement for your fellow developers
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to access the repository. You can use CVS's SSH and ext method. Simply add
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the user to the server's list of users, add the user to the file WRITERS, and
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then they can do the following:
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$ export CVS_RSH='/usr/bin/ssh'
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$ cvs -d :ext:username@server.hostname:/cvs/root login
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This is a much more secure way for developers to access the repository.
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-----------------------------------------------------------------------------
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4.2. Anonymous CVS access by http
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There is another way to allow anonymous access to CVS. If there is an http
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server and Python installed on the server, you can use a set of Python CGI
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scripts called [http://viewcvs.sourceforge.net] viewcvs, which allow people
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to view the CVS repository over the web, and can generate tarballs for users
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to download.
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There is also a set of Perl CGI scripts that do the same thing called
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[http://stud.fh-heilbronn.de/~zeller/cgi/cvsweb.cgi/] cvsweb, but Viewcvs
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is more mature and is preferred (at least by me).
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-----------------------------------------------------------------------------
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4.3. CVSGrab
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[http://cvsgrab.sourceforge.net] CVSGrab is an end-user tool for
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downloading the CVS repository by a ViewCVS interface. It is very useful when
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you are behind a corporate firewall that blocks the Pserver, as you can just
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grab the repository over standard HTTP. The only problem is if it doesn't
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have a ViewCVS interface, but most free software repositories are now on the
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web, and the few that still use cvsweb seem to be switching over to ViewCVS.
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CVSGrab is written in Java, which may at first be a turn-off to some people
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(it is to me), but it seems completely compilable using GCJ, the Java
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front-end to GCC.
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CVSGrab is a tool that goes hand-in-hand with ViewCVS. It is an end-user
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tool, not one that you as a system administrator or repository administrator
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would set up and configure.
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-----------------------------------------------------------------------------
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5. Acknowledgements
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This Mini-HOWTO was written by Morgon Kanter, who is reachable at <morgon
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AT surgo DOT net>, public key available from [http://www.surgo.net/
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pubkey.asc] http://www.surgo.net/pubkey.asc. Email all problems with this
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document to him, and they will be fixed ASAP.
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My thanks goes out to all the people who contributed to CVS over the years,
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as well as the creators of Viewcvs, and in turn the creators of cvsweb who
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inspired it.
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I would also like to thank Tabatha Persad for reviewing and helping me edit
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this monster, as well as putting up with me. Thanks!
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Also thanks to the various email contributors who pointed out missing
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stuff. Thank you Y Giridhar Appaji Nag and Pasi Hirvonen!
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-----------------------------------------------------------------------------
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6. GNU Free Documentation License
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GNU Free Documentation License
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Version 1.2, November 2002
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Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
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59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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Everyone is permitted to copy and distribute verbatim copies
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of this license document, but changing it is not allowed.
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0. PREAMBLE
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The purpose of this License is to make a manual, textbook, or other
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functional and useful document "free" in the sense of freedom: to
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assure everyone the effective freedom to copy and redistribute it,
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with or without modifying it, either commercially or noncommercially.
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Secondarily, this License preserves for the author and publisher a way
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to get credit for their work, while not being considered responsible
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for modifications made by others.
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This License is a kind of "copyleft", which means that derivative
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works of the document must themselves be free in the same sense. It
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complements the GNU General Public License, which is a copyleft
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license designed for free software.
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We have designed this License in order to use it for manuals for free
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software, because free software needs free documentation: a free
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program should come with manuals providing the same freedoms that the
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software does. But this License is not limited to software manuals;
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it can be used for any textual work, regardless of subject matter or
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whether it is published as a printed book. We recommend this License
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principally for works whose purpose is instruction or reference.
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1. APPLICABILITY AND DEFINITIONS
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This License applies to any manual or other work, in any medium, that
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contains a notice placed by the copyright holder saying it can be
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distributed under the terms of this License. Such a notice grants a
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world-wide, royalty-free license, unlimited in duration, to use that
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work under the conditions stated herein. The "Document", below,
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refers to any such manual or work. Any member of the public is a
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licensee, and is addressed as "you". You accept the license if you
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copy, modify or distribute the work in a way requiring permission
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under copyright law.
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A "Modified Version" of the Document means any work containing the
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Document or a portion of it, either copied verbatim, or with
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modifications and/or translated into another language.
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A "Secondary Section" is a named appendix or a front-matter section of
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the Document that deals exclusively with the relationship of the
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publishers or authors of the Document to the Document's overall subject
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(or to related matters) and contains nothing that could fall directly
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within that overall subject. (Thus, if the Document is in part a
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textbook of mathematics, a Secondary Section may not explain any
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mathematics.) The relationship could be a matter of historical
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connection with the subject or with related matters, or of legal,
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commercial, philosophical, ethical or political position regarding
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them.
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The "Invariant Sections" are certain Secondary Sections whose titles
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are designated, as being those of Invariant Sections, in the notice
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that says that the Document is released under this License. If a
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section does not fit the above definition of Secondary then it is not
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allowed to be designated as Invariant. The Document may contain zero
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Invariant Sections. If the Document does not identify any Invariant
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Sections then there are none.
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The "Cover Texts" are certain short passages of text that are listed,
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as Front-Cover Texts or Back-Cover Texts, in the notice that says that
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the Document is released under this License. A Front-Cover Text may
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be at most 5 words, and a Back-Cover Text may be at most 25 words.
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A "Transparent" copy of the Document means a machine-readable copy,
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represented in a format whose specification is available to the
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general public, that is suitable for revising the document
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straightforwardly with generic text editors or (for images composed of
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pixels) generic paint programs or (for drawings) some widely available
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drawing editor, and that is suitable for input to text formatters or
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for automatic translation to a variety of formats suitable for input
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to text formatters. A copy made in an otherwise Transparent file
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format whose markup, or absence of markup, has been arranged to thwart
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or discourage subsequent modification by readers is not Transparent.
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An image format is not Transparent if used for any substantial amount
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of text. A copy that is not "Transparent" is called "Opaque".
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Examples of suitable formats for Transparent copies include plain
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ASCII without markup, Texinfo input format, LaTeX input format, SGML
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or XML using a publicly available DTD, and standard-conforming simple
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HTML, PostScript or PDF designed for human modification. Examples of
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transparent image formats include PNG, XCF and JPG. Opaque formats
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include proprietary formats that can be read and edited only by
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proprietary word processors, SGML or XML for which the DTD and/or
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processing tools are not generally available, and the
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machine-generated HTML, PostScript or PDF produced by some word
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processors for output purposes only.
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The "Title Page" means, for a printed book, the title page itself,
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plus such following pages as are needed to hold, legibly, the material
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this License requires to appear in the title page. For works in
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formats which do not have any title page as such, "Title Page" means
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the text near the most prominent appearance of the work's title,
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preceding the beginning of the body of the text.
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A section "Entitled XYZ" means a named subunit of the Document whose
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title either is precisely XYZ or contains XYZ in parentheses following
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text that translates XYZ in another language. (Here XYZ stands for a
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specific section name mentioned below, such as "Acknowledgements",
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"Dedications", "Endorsements", or "History".) To "Preserve the Title"
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of such a section when you modify the Document means that it remains a
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section "Entitled XYZ" according to this definition.
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The Document may include Warranty Disclaimers next to the notice which
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states that this License applies to the Document. These Warranty
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Disclaimers are considered to be included by reference in this
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License, but only as regards disclaiming warranties: any other
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implication that these Warranty Disclaimers may have is void and has
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no effect on the meaning of this License.
|
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|
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|
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2. VERBATIM COPYING
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|
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You may copy and distribute the Document in any medium, either
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commercially or noncommercially, provided that this License, the
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copyright notices, and the license notice saying this License applies
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to the Document are reproduced in all copies, and that you add no other
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conditions whatsoever to those of this License. You may not use
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technical measures to obstruct or control the reading or further
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copying of the copies you make or distribute. However, you may accept
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compensation in exchange for copies. If you distribute a large enough
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number of copies you must also follow the conditions in section 3.
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|
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You may also lend copies, under the same conditions stated above, and
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you may publicly display copies.
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||
|
||
|
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3. COPYING IN QUANTITY
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|
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If you publish printed copies (or copies in media that commonly have
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printed covers) of the Document, numbering more than 100, and the
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Document's license notice requires Cover Texts, you must enclose the
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copies in covers that carry, clearly and legibly, all these Cover
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Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
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the back cover. Both covers must also clearly and legibly identify
|
||
you as the publisher of these copies. The front cover must present
|
||
the full title with all words of the title equally prominent and
|
||
visible. You may add other material on the covers in addition.
|
||
Copying with changes limited to the covers, as long as they preserve
|
||
the title of the Document and satisfy these conditions, can be treated
|
||
as verbatim copying in other respects.
|
||
|
||
If the required texts for either cover are too voluminous to fit
|
||
legibly, you should put the first ones listed (as many as fit
|
||
reasonably) on the actual cover, and continue the rest onto adjacent
|
||
pages.
|
||
|
||
If you publish or distribute Opaque copies of the Document numbering
|
||
more than 100, you must either include a machine-readable Transparent
|
||
copy along with each Opaque copy, or state in or with each Opaque copy
|
||
a computer-network location from which the general network-using
|
||
public has access to download using public-standard network protocols
|
||
a complete Transparent copy of the Document, free of added material.
|
||
If you use the latter option, you must take reasonably prudent steps,
|
||
when you begin distribution of Opaque copies in quantity, to ensure
|
||
that this Transparent copy will remain thus accessible at the stated
|
||
location until at least one year after the last time you distribute an
|
||
Opaque copy (directly or through your agents or retailers) of that
|
||
edition to the public.
|
||
|
||
It is requested, but not required, that you contact the authors of the
|
||
Document well before redistributing any large number of copies, to give
|
||
them a chance to provide you with an updated version of the Document.
|
||
|
||
|
||
4. MODIFICATIONS
|
||
|
||
You may copy and distribute a Modified Version of the Document under
|
||
the conditions of sections 2 and 3 above, provided that you release
|
||
the Modified Version under precisely this License, with the Modified
|
||
Version filling the role of the Document, thus licensing distribution
|
||
and modification of the Modified Version to whoever possesses a copy
|
||
of it. In addition, you must do these things in the Modified Version:
|
||
|
||
A. Use in the Title Page (and on the covers, if any) a title distinct
|
||
from that of the Document, and from those of previous versions
|
||
(which should, if there were any, be listed in the History section
|
||
of the Document). You may use the same title as a previous version
|
||
if the original publisher of that version gives permission.
|
||
B. List on the Title Page, as authors, one or more persons or entities
|
||
responsible for authorship of the modifications in the Modified
|
||
Version, together with at least five of the principal authors of the
|
||
Document (all of its principal authors, if it has fewer than five),
|
||
unless they release you from this requirement.
|
||
C. State on the Title page the name of the publisher of the
|
||
Modified Version, as the publisher.
|
||
D. Preserve all the copyright notices of the Document.
|
||
E. Add an appropriate copyright notice for your modifications
|
||
adjacent to the other copyright notices.
|
||
F. Include, immediately after the copyright notices, a license notice
|
||
giving the public permission to use the Modified Version under the
|
||
terms of this License, in the form shown in the Addendum below.
|
||
G. Preserve in that license notice the full lists of Invariant Sections
|
||
and required Cover Texts given in the Document's license notice.
|
||
H. Include an unaltered copy of this License.
|
||
I. Preserve the section Entitled "History", Preserve its Title, and add
|
||
to it an item stating at least the title, year, new authors, and
|
||
publisher of the Modified Version as given on the Title Page. If
|
||
there is no section Entitled "History" in the Document, create one
|
||
stating the title, year, authors, and publisher of the Document as
|
||
given on its Title Page, then add an item describing the Modified
|
||
Version as stated in the previous sentence.
|
||
J. Preserve the network location, if any, given in the Document for
|
||
public access to a Transparent copy of the Document, and likewise
|
||
the network locations given in the Document for previous versions
|
||
it was based on. These may be placed in the "History" section.
|
||
You may omit a network location for a work that was published at
|
||
least four years before the Document itself, or if the original
|
||
publisher of the version it refers to gives permission.
|
||
K. For any section Entitled "Acknowledgements" or "Dedications",
|
||
Preserve the Title of the section, and preserve in the section all
|
||
the substance and tone of each of the contributor acknowledgements
|
||
and/or dedications given therein.
|
||
L. Preserve all the Invariant Sections of the Document,
|
||
unaltered in their text and in their titles. Section numbers
|
||
or the equivalent are not considered part of the section titles.
|
||
M. Delete any section Entitled "Endorsements". Such a section
|
||
may not be included in the Modified Version.
|
||
N. Do not retitle any existing section to be Entitled "Endorsements"
|
||
or to conflict in title with any Invariant Section.
|
||
O. Preserve any Warranty Disclaimers.
|
||
|
||
If the Modified Version includes new front-matter sections or
|
||
appendices that qualify as Secondary Sections and contain no material
|
||
copied from the Document, you may at your option designate some or all
|
||
of these sections as invariant. To do this, add their titles to the
|
||
list of Invariant Sections in the Modified Version's license notice.
|
||
These titles must be distinct from any other section titles.
|
||
|
||
You may add a section Entitled "Endorsements", provided it contains
|
||
nothing but endorsements of your Modified Version by various
|
||
parties--for example, statements of peer review or that the text has
|
||
been approved by an organization as the authoritative definition of a
|
||
standard.
|
||
|
||
You may add a passage of up to five words as a Front-Cover Text, and a
|
||
passage of up to 25 words as a Back-Cover Text, to the end of the list
|
||
of Cover Texts in the Modified Version. Only one passage of
|
||
Front-Cover Text and one of Back-Cover Text may be added by (or
|
||
through arrangements made by) any one entity. If the Document already
|
||
includes a cover text for the same cover, previously added by you or
|
||
by arrangement made by the same entity you are acting on behalf of,
|
||
you may not add another; but you may replace the old one, on explicit
|
||
permission from the previous publisher that added the old one.
|
||
|
||
The author(s) and publisher(s) of the Document do not by this License
|
||
give permission to use their names for publicity for or to assert or
|
||
imply endorsement of any Modified Version.
|
||
|
||
|
||
5. COMBINING DOCUMENTS
|
||
|
||
You may combine the Document with other documents released under this
|
||
License, under the terms defined in section 4 above for modified
|
||
versions, provided that you include in the combination all of the
|
||
Invariant Sections of all of the original documents, unmodified, and
|
||
list them all as Invariant Sections of your combined work in its
|
||
license notice, and that you preserve all their Warranty Disclaimers.
|
||
|
||
The combined work need only contain one copy of this License, and
|
||
multiple identical Invariant Sections may be replaced with a single
|
||
copy. If there are multiple Invariant Sections with the same name but
|
||
different contents, make the title of each such section unique by
|
||
adding at the end of it, in parentheses, the name of the original
|
||
author or publisher of that section if known, or else a unique number.
|
||
Make the same adjustment to the section titles in the list of
|
||
Invariant Sections in the license notice of the combined work.
|
||
|
||
In the combination, you must combine any sections Entitled "History"
|
||
in the various original documents, forming one section Entitled
|
||
"History"; likewise combine any sections Entitled "Acknowledgements",
|
||
and any sections Entitled "Dedications". You must delete all sections
|
||
Entitled "Endorsements".
|
||
|
||
|
||
6. COLLECTIONS OF DOCUMENTS
|
||
|
||
You may make a collection consisting of the Document and other documents
|
||
released under this License, and replace the individual copies of this
|
||
License in the various documents with a single copy that is included in
|
||
the collection, provided that you follow the rules of this License for
|
||
verbatim copying of each of the documents in all other respects.
|
||
|
||
You may extract a single document from such a collection, and distribute
|
||
it individually under this License, provided you insert a copy of this
|
||
License into the extracted document, and follow this License in all
|
||
other respects regarding verbatim copying of that document.
|
||
|
||
|
||
7. AGGREGATION WITH INDEPENDENT WORKS
|
||
|
||
A compilation of the Document or its derivatives with other separate
|
||
and independent documents or works, in or on a volume of a storage or
|
||
distribution medium, is called an "aggregate" if the copyright
|
||
resulting from the compilation is not used to limit the legal rights
|
||
of the compilation's users beyond what the individual works permit.
|
||
When the Document is included an aggregate, this License does not
|
||
apply to the other works in the aggregate which are not themselves
|
||
derivative works of the Document.
|
||
|
||
If the Cover Text requirement of section 3 is applicable to these
|
||
copies of the Document, then if the Document is less than one half of
|
||
the entire aggregate, the Document's Cover Texts may be placed on
|
||
covers that bracket the Document within the aggregate, or the
|
||
electronic equivalent of covers if the Document is in electronic form.
|
||
Otherwise they must appear on printed covers that bracket the whole
|
||
aggregate.
|
||
|
||
|
||
8. TRANSLATION
|
||
|
||
Translation is considered a kind of modification, so you may
|
||
distribute translations of the Document under the terms of section 4.
|
||
Replacing Invariant Sections with translations requires special
|
||
permission from their copyright holders, but you may include
|
||
translations of some or all Invariant Sections in addition to the
|
||
original versions of these Invariant Sections. You may include a
|
||
translation of this License, and all the license notices in the
|
||
Document, and any Warrany Disclaimers, provided that you also include
|
||
the original English version of this License and the original versions
|
||
of those notices and disclaimers. In case of a disagreement between
|
||
the translation and the original version of this License or a notice
|
||
or disclaimer, the original version will prevail.
|
||
|
||
If a section in the Document is Entitled "Acknowledgements",
|
||
"Dedications", or "History", the requirement (section 4) to Preserve
|
||
its Title (section 1) will typically require changing the actual
|
||
title.
|
||
|
||
|
||
9. TERMINATION
|
||
|
||
You may not copy, modify, sublicense, or distribute the Document except
|
||
as expressly provided for under this License. Any other attempt to
|
||
copy, modify, sublicense or distribute the Document is void, and will
|
||
automatically terminate your rights under this License. However,
|
||
parties who have received copies, or rights, from you under this
|
||
License will not have their licenses terminated so long as such
|
||
parties remain in full compliance.
|
||
|
||
|
||
10. FUTURE REVISIONS OF THIS LICENSE
|
||
|
||
The Free Software Foundation may publish new, revised versions
|
||
of the GNU Free Documentation License from time to time. Such new
|
||
versions will be similar in spirit to the present version, but may
|
||
differ in detail to address new problems or concerns. See
|
||
http://www.gnu.org/copyleft/.
|
||
|
||
Each version of the License is given a distinguishing version number.
|
||
If the Document specifies that a particular numbered version of this
|
||
License "or any later version" applies to it, you have the option of
|
||
following the terms and conditions either of that specified version or
|
||
of any later version that has been published (not as a draft) by the
|
||
Free Software Foundation. If the Document does not specify a version
|
||
number of this License, you may choose any version ever published (not
|
||
as a draft) by the Free Software Foundation.
|
||
|
||
|
||
ADDENDUM: How to use this License for your documents
|
||
|
||
To use this License in a document you have written, include a copy of
|
||
the License in the document and put the following copyright and
|
||
license notices just after the title page:
|
||
|
||
Copyright (c) YEAR YOUR NAME.
|
||
Permission is granted to copy, distribute and/or modify this document
|
||
under the terms of the GNU Free Documentation License, Version 1.2
|
||
or any later version published by the Free Software Foundation;
|
||
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
|
||
A copy of the license is included in the section entitled "GNU
|
||
Free Documentation License".
|
||
|
||
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
|
||
replace the "with...Texts." line with this:
|
||
|
||
with the Invariant Sections being LIST THEIR TITLES, with the
|
||
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
|
||
|
||
If you have Invariant Sections without Cover Texts, or some other
|
||
combination of the three, merge those two alternatives to suit the
|
||
situation.
|
||
|
||
If your document contains nontrivial examples of program code, we
|
||
recommend releasing these examples in parallel under your choice of
|
||
free software license, such as the GNU General Public License,
|
||
to permit their use in free software.
|
||
|
||
|
||
Notes
|
||
|
||
[1] info cvs, if you have the stand-alone info viewer installed on your
|
||
system
|