Marc Fournier Tom Lane Thomas Lockhart David Fetter 1999-05-20 The PostgreSQL source code is stored and managed using the CVS version control system. An official mirror using Git is also available, for those who wish to use a distributed version control system. This mirror is automatically updated whenever the main repository changes, so it always contains the latest versions of all branches. Using git is the most flexible way to work with the source, and it allows you to work offline without having constant access to the project servers. rsync based cvs also lets you work offline, but lacks many of the other advantages of git. Our Wiki, and , has additional details on working with CVS and Git. With git you will make a copy of the entire code repository to your local machine, so you will have access to all history and branches offline. This is the fastest and most flexible way to develop or test patches. You will need an installed version of git, which you can get from . Many systems also have a recent version of git installed by default, or available in their package repository system. To being using the git repository, make a clone of the official mirror: git clone git://git.postgresql.org/git/postgresql.git This will copy the full repository to your local machine, so it may take a while to complete, especially if you have a slow internet connection. The git mirror can also be reached via the http protocol in case for example a firewall is blocking access to the git protocol. Just replace the URL like: git clone http://git.postgresql.org/git/postgresql.git The http protocol is less efficient than the git protocol, so it will be slightly slower to use. Whenever you want to get the latest updates in the system, cd into the repository, and run: git fetch git can do a lot more things than just fetch the source. For more information, consult the man pages for the product, or the website at . If you would like to keep up with the current sources on a regular basis, you can fetch them from our CVS server and then use CVS to retrieve updates from time to time. You will need a local copy of CVS (Concurrent Version Control System), which you can get from (the official site with the latest version) or any GNU software archive site (often somewhat outdated). Many systems have a recent version of cvs installed by default. Do an initial login to the CVS server: cvs -d :pserver:anoncvs@anoncvs.postgresql.org:/projects/cvsroot login You will be prompted for a password; you can enter anything except an empty string. You should only need to do this once, since the password will be saved in .cvspass in your home directory. Fetch the PostgreSQL sources: cvs -z3 -d :pserver:anoncvs@anoncvs.postgresql.org:/projects/cvsroot co -P pgsql This installs the PostgreSQL sources into a subdirectory pgsql of the directory you are currently in. This initial checkout is a little slower than simply downloading a tar.gz file. The advantage of CVS doesn't show up until you want to update the file set later on. Whenever you want to update to the latest CVS sources, cd into the pgsql subdirectory, and issue: cvs -z3 update -d -P This will fetch only the changes since the last time you updated. You can update in just a couple of minutes, typically, even over a modem-speed line. You can save yourself some typing by making a file .cvsrc in your home directory that contains: cvs -z3 update -d -P This supplies the -z3 option to all cvs commands, and the -d and -P options to cvs update. Then you just have to say: cvs update to update your files. CVS can do a lot of other things, such as fetching prior revisions of the PostgreSQL sources rather than the latest development version. For more info consult the manual that comes with CVS, or see the online documentation at . CVS has deficiencies. For example, generating diffs that add or remove files requires write access to the CVS repository. To work around that deficiency, use cvsutils, which is packaged in several operating systems, and is available in source form at , or use git or another system designed to work offline. Note that building PostgreSQL from a CVS pull requires reasonably up-to-date versions of bison and flex, which are not needed to build from a distribution tarball because the files made with them are pre-built in a tarball. You will need Perl as well. Otherwise the tool requirements are the same as building from source. An alternative to using anonymous CVS for retrieving the PostgreSQL source tree is rsync, an incremental file transfer tool. A major advantage to using rsync instead of plain cvs is that it can reliably replicate the entire CVS repository on your local system, allowing fast local access to cvs operations such as log and diff. Other advantages include fast synchronization to the PostgreSQL server due to an efficient streaming transfer protocol which only sends the changes since the last update. You can download the CVS repository using this command: rsync -avzH --delete anoncvs.postgresql.org::pgsql-cvs cvsroot/ For full instructions, see the "rsync" section in the pgbuildfarm instructions.