How to use SVN

SVN is a program which keeps track of all the different versions of our source files. People familiar with its predecessor, cvs should read on. This documentation is written because of our transition to SVN. When the transition period is over, we will rewrite these pages. While waiting, this page will contain information useful for our present cvs users.

Our main subversion repository is at the address Subversion documentation is available as a browsable book.

Subversion communicates with us in cryptical ways. m is "me", and u is you, right? Here is the full story:


Graphical Subversion clients

If you want to use a graphical Subversion client, the recommended clients are documented on the following pages:

There are also other clients for which we have written some documentation, but the documentation is outdated, and some of the clients are not actively supported anymore:

Please follow the recommendations for daily routines at the end of this document!

Use svn on the command line

To check out means that you copy all the documents that our projects are working on to your computer.

The first commands

This may be done in two ways:

  1. You want to check out the files for only one or a limited number of languages. In that case, follow these instructions, especially the section "Only the GT core and the wanted language(s)".
  2. You work on many languages and / or many end user projects (dictionaries, Oahpa, ...). In that case, read on.
  3. To control exactly what you need from our svn, use the options --depth and --set-depth. More info on Stack Overflow

Thus, to check o to your home directory (write cd), and give the following command:

svn co main --username <your_username>

... where you have replaced <your_username> with the username you have aquired from the admin. This will enable you to check in your work. If you don't have a user name or just want to browse our code, just skip the username.

After you have checked out, please run the following script, and follow the on-screen instructions:


With the above commands, you have now on your local computer a copy of the source code and the environment is set up properly.

There are also other svn repositories that may be checked out, with the same command. Some of them are closed, and you need a password to access them. Here are the open ones:

svn co freecorpus  # corpus files for many languages, mainly Saami 
svn co rusfree        # corpus files for languages in Russia
svn co biggies        # large files

They may be checked out with the same command as for langtech above.

Frequently used commands

Now that you have checked out your repository, you can use a set of commands to manipulate your copy of the source code. We recommend to always update the repository before you begin to edit files inside it. After having edited some files you usually want to have an overview of which files have been modified. To share our work with the others we check in our work. We can also add, delete, move and copy files inside the repository. A brief overview of the commands needed for these actions is given below, for further details see the references at the end of this document.

Update your working copy
svn up
Schedule a file for addition
svn add filename
Schedule a file for deletion
svn delete filename
You may also copy and move files and directories with these two commands, but read about them in the svn book first:
svn copy filename
svn move filename
Examine your changes
svn status
Examine the file history
svn log FILE
Change the commit message for a specific revision
svn propedit svn:log --revprop -r REV FILE
This will bring up the existing log text for the specified revision in your default editor (typically Emacs), where you can edit and change it as you want. This is useful if you accidentally committed some changes with an empty or uninformative log message.
Compare your modified file to the version in the repository
svn diff FILE
Compare some earlier versions, say here versions 123 and 120
svn diff -r 123:120 FILE
Undo your local changes (ie revert to the repository status)
svn revert FILE
Resolve Conflicts (Merge Others' Changes)
svn update
svn resolved
Commit your changes
svn ci -m "Your description of the changes here." FILE
(Note that the above changes, add, delete, copy, move, must all be committed by ci in order to take effect)

Ignoring items

The key insight to understanding svn ignore can be summarised in two sentences (quoting Joseph Pecoraro's excellent article):

You don’t svn:ignore a file. You put an svn:ignore property on the directory to ignore that filename pattern!

Here is the command for making directories ignoring files, assuming you want to ignore files in the directory where you stand now:

$ svn propedit svn:ignore .

Then add the files or suffixes you want to ignore (e.g. *.toc), and save (if in emacs: ctrl X C). Then you must check in the directory (here represented by the "."):

$ svn ci -m "Vi ignorerer toc-filer" .

More details about ignoring files can be found in Chapter 3: Advanced Topics, in the section Ignoring Unversioned Items, in the SVN book.

Daily routines

  • Update in the morning, and allways before you check in.
  • Always check in the files at the end of the day.
  • If you know that other people are working on the same file, you should check in several times a day.
  • Check in after you have done major revisions.
  • Remember to compile the program before you check in, so that you know you do not check in a defect file.

What do I write in the log message

The best way to learn to write good log messages is to read other log messages. Pick a file (e.g. twol-sme.txt, sme-lex.fst), and read the log (the command is svn log filename | less). If the log message tells you what you want to know, then it is a good log message.

In svn it is possible to edit and correct bad log messages. See the list of useful commands above for how to do this.

Digging out svn deleted files from the repository

After you did svn rm file, svn ci -m removed file, the file is still there. To get it, do the following:

  • First find the number of the deletion, by logging the parent folder, with the flag -v: svn log -v parentfollder/ |less (Deletion was some number, say r61000)
  • Then get the deleted file with the command: svn cat url/of/file@lastrevisionthefileexisted -r latrevisionthefileexisted > file
  • thus: svn cat -r 62505 > asdf

Revert back to an earlier version of a file

Read this.

Further reading

The Basic work cycle in the SVN book covers daily usage in great detail. Appendix B covers some details for users accustomed to CVS.

The RapidSVN wiki has a tutorial that covers our daily usage pattern.