GraphicsMagick CVS

The GraphicsMagick source is available via anonymous CVS. This is a convenient way for developers from around the country or world to download the GraphicsMagick source, fix bugs, or add new features.

What is CVS

CVS is the Concurrent Version System and is a very popular version control tool for software projects. It is designed to allow multiple authors to be able to simultaneously operate on the same source tree. This source tree is centrally maintained, but each developer has a local mirror of this repository that they make their changes to.

CVSWeb Access

A CVSWeb interface is available which may be used to interactively view the latest versions of files, or the changes to files, using your web browser.

CVS Command Summary

Here is a summary of CVS commands. See the CVS Home Page for detailed information and documentation about CVS. The command cvs –help-commands will print out all of the available commands. The command cvs <command> –help will cause a help message to be printed for the specified <command>.

Action	Result
add	Add a new file or directory to the repository.
checkout	Make a working directory of source files for editing.
commit	Apply changes to the source repository (write access).
diff	Show differences between local files and the source repository.
history	Show reports on cvs commands against the source repository.
log	Display CVS log information.
rdiff	Prepare a collection of differences reflecting changes between release.
status	Show current status of files in the repository and local copies.
update	Bring your working directory up to date with the repository.

Using Anonymous CVS

A live source tree for GraphicsMagick is available from cvs.graphicsmagick.org. This source tree may be retrieved over the network using the CVS program. Microsoft Windows users may be interested in TortoiseCVS, which transparently extends the Windows file manager to support CVS. There are currently two CVS protocols available for use: 'EXT' and 'PSERVER'. The 'EXT' protocol is used on top of encrypted SSH so it is very secure. The 'PSERVER' protocol uses simple TCP and plain-text passwords so it is not very secure. GraphicsMagick CVS is in the process of transitioning to using SSH access only (due to security concerns), so using the EXT protocol is recommended. Some corporate firewalls do not allow outbound PSERVER connections (to TCP port 2401) while they do allow SSH connections.

The protocol to use is indicated by the prefix of the CVSROOT specification. The CVSROOT specification may be specified via the CVSROOT environment variable or as an argument to the cvs -d option. The necessary CVSROOT specifications are shown in the following table.

Protocol	CVSROOT Specification
EXT	:ext:anoncvs@cvs.graphicsmagick.org:/GraphicsMagick
PSERVER	:pserver:anonymous@cvs.graphicsmagick.org:/GraphicsMagick

To specify the cvs root directly on the command line:

cvs -d :pserver:anonymous@cvs.graphicsmagick.org:/GraphicsMagick command args...

Or to set as an environment variable:

export CVSROOT=:ext:anoncvs@cvs.graphicsmagick.org:/GraphicsMagick
setenv CVSROOT :ext:anoncvs@cvs.graphicsmagick.org:/GraphicsMagick

When using the PSERVER protocol, a CVS login is needed prior to checking out the sources:

cvs login

This will ask you for a password. The password is anonymous. Enter it and press Return. The EXT protocol does not currently require a password when used for anonymous access.

The CVS program supports a configuration file ($HOME/.cvsrc). Many command options used in the remaining instructions may be set as defaults (so they don't need to be repeated) by creating a .cvsrc file in your home directory with the following contents:

cvs -z3
update -P -d
checkout -P
diff -u

To get the tree and place it in a sub-directory of your current working directory, issue the command:

cvs co -P GraphicsMagick

Or to save bandwidth get the compressed version, type:

cvs -z3 co -P GraphicsMagick

Note that adding -r GraphicsMagick-1_3 requests the sources from the GraphicsMagick 1.3 release branch.

To update the sources within a checked out directory execute:

cvs update -P -d

and only the files which have changed will be updated.

The available modules relating to GraphicsMagick are:

GraphicsMagick (core sources)
GraphicsMagick-NT (everything needed for Microsoft Windows)
GraphicsMagick-World (everything related to GraphicsMagick)

To check out the GraphicsMagick source for Microsoft Windows, try this command line:

cvs -z3 co -P -r GraphicsMagick-1_3 GraphicsMagick-NT

If you require a specific release of GraphicsMagick (e.g. 1.3.3), you may check it out like:

cvs -z3 co-r GraphicsMagick-1_3_3 -P GraphicsMagick

where the GraphicsMagick-1_3_3 is the release tag. You can use:

cvs status -v README.txt

from within an existing checked out directory to see what branch and release tags are available.

You can use:

cvs -z3 update -r GraphicsMagick-1_3_3

from within an existing checked out directory to move it up (or down) to that branch or release tag.

Checking out from release tag, or updating to a release tag, causes the "sticky" flag to be set on checked out files so that further update requests will only cause an update if the tag is a branch tag, and is a newer version on the branch. To clear the sticky flags and update to the most current version on the trunk, use:

cvs -z3 update -A

Once a release has been tagged, checking out or updating using a release tag is the only reliable way to obtain release files from CVS since the default is to check out the most current sources on the requested branch, which may not be stable or released.

Using compression levels over -z3 may slow the CVS transfer since they require the CVS server to work much harder, yet don't compress the data much more.

CVS Software

The best place to look for the latest version of CVS is at the CVS Home Page. There is also a lot of information and documentation about CVS available on numerous other web sites.