CVS to SVN Crossover Guide
Purpose
This document provides an alternate method of learning Subversion.
   Many users dislike learning new technology via a theoretical "top
   down" approach, as provided by the Subversion Book.  Instead,
   this document presents Subversion from the "bottom up": it shows a
   CVS command or task, and then shows the equivalent task in
   Subversion (along with relevant book links.) It's essentially a
   re-indexing of topics covered by the book, keyed on CVS tasks.
 
Table of Contents
Setup
Basic Work Cycle
Examining history
  - Seeing history of an item
- Comparing two versions of an item
Branching/Tagging/Merging
  - Creating a branch
- Moving a working copy to a branch
- Finding the beginning of a branch
- Porting a single change
- Merging a whole branch
- Reverting a committed change
- Resurrecting deleted items
- Creating a tag
- Tweaking a tag
- Seeing all tags
- Comparing two tags
- Seeing logs between two tags
Other tasks
  - Using modules
- Line endings and keywords
 
Repository creation
Create a new repository for holding versioned data.
  | CVS | Subversion | 
  | 
      Commands:$ cvs -d /usr/local/repos initExplanation:Creates a new directory repos ready to hold RCS
          files and config scripts. | 
      Commands:$ svnadmin create /usr/local/reposExplanation:Creates a new directory repos containing BerkeleyDB
          files and config scripts. | 
  - Book References:
- Repository Creation and Configuration
 
Importing data
Populate a new repository with initial data.  Assuming that you
   have a tree of code in the local directory myproj/, and
   you want to move this tree into the repository.
  | CVS | Subversion | 
  | 
      Commands:$ cd myproj$ cvs -d /usr/local/repos import myproj/ none startExplanation:This copies the contents of the current working directory to
      a new directory (myproj) in the CVS repository.  The
      CVS repository now contains a directory /myproj/ at the
      top level. | 
      Commands:$ svn mkdir file:///usr/local/repos/tags$ svn mkdir file:///usr/local/repos/branches$ svn import myproj/ file:///usr/local/repos/trunkExplanation:Though not strictly required, we deliberately create
      /tags and /branches top-level directories in
      the repository, to hold tags and branches later on.  Then we
      import the contents of the local myproj/ directory into
      a newly created /trunk directory in the
      repository. | 
  - Book References:
- Choosing a repository layout
- svn import
 
Installing a server
Make the repository available to clients via a network.
  | CVS | Subversion | 
  | 
      Commands:(too complex to demonstrate here)Explanation:Export the repository via the cvs pserver program.
      It can be launched by either inetd or a
      client's ssh remote request. | 
      Commands:(too complex to demonstrate here)Explanation:Export the repository with the Apache 2.0.x server,
      or via the svnserve program.  The latter can run as a
      standalone daemon, can be launched by inetd, or
      invoked by a client's ssh remote request. | 
  - Book References:
- Server configuration
 
Authenticating to a server
Have a network client prove its identity to a version
      control server.
  | CVS | Subversion | 
  | 
      Commands:$ cvs -d :pserver:user@host:/repos command…Explanation:When contacting a repository, the client pre-emptively
      "pushes" its authentication credentials at the server. | 
      Commands:$ svn command URL…Password for 'user':  XXXXXXXExplanation:The client's authentication credentials are "pulled" from
      the user interactively, and only when the server deems that a
      challenge needs to be made.  (And contrary to popular belief,
      the --username and --password options are
      merely values to be used if the server issues a
      challenge; they do not "push" the credentials at the
      server.) | 
  - Book References:
- Network Model
 
Browsing a repository
Browse the repository as a filesystem, perusing file
      contents and history as well (older versions of files or
      trees.)
  | CVS | Subversion | 
  | 
      Commands:(not possible with commandline client)Explanation:Not possible with commandline client.  A third-party web
      server tool such as ViewCVS must be used. | 
      Commands:$ svn list URL [-r rev] [-v]$ svn cat URL [-r rev]Explanation:The svn list and svn cat commands allow
      interactive browsing of a repository (and all previous states of
      a repository) from the commandline.  (The --verbose [-v]
      switch displays full listing information.)  If Apache is being
      used as a Subversion server process (i.e. clients access via
      http://), then the latest version of the
      repository can be directly browsed by entering URL into
      any web browser.  Additionally, a third-party web server tool
      (such as ViewCVS) can be used with Subversion. | 
  - Book References:
- svn list
 
Checking out a working copy
Create a workspace on local disk which mirrors a directory
      in the repository.
  | CVS | Subversion | 
  | 
      Commands:$ cvs -d /usr/local/repos checkout myprojU myproj/foo.cU myproj/bar.c…Explanation:Creates a local directory myproj which is a mirror
      of the repository directory /myproj. | 
      Commands:$ svn checkout file:///usr/local/repos/trunk myprojA  myproj/foo.cA  myproj/bar.c…Explanation:Assuming that the original project data was imported into
      the repository /trunk directory, this creates a local
      directory myproj which is a mirror of the repository
      directory /trunk.  Standard Subversion convention is to
      do "mainline" development in /trunk.  See branching and
      tagging sections for more details. | 
  - Book References:
- Initial Checkout
- svn checkout
 
Seeing locally changed items
Discover which items in the working copy have local
      modifications or are scheduled for addition/deletion.
  | CVS | Subversion | 
  | 
      Commands:$ cvs status…File: baz.c   Status: Up-to-date…$ cvs updateM foo.cU bar.c…Explanation:The cvs status command shows whether a file is
      locally modified or out of date, including information about
      working revision and branch info.  Unfortunately, because the
      output is so verbose and hard to read, many users run cvs
      update instead, which shows a more compact listing of
      modified files (and of course, it also causes the server to
      merge changes into your working copy.) | 
      Commands:$ svn statusM     foo.c…Explanation:Shows modified files only.  Very fast, as it does not use
      the network.  Does not update your working copy, yet still shows
      a single-line display, much like svn update.  To see
      working revision and branch information, run svn info. | 
  - Book References:
- Examine Your Changes
- svn status
 
Seeing out-of-date items
Discover which items in the working copy are out-of-date
      (i.e. newer versions exist in the repository.)
  | CVS | Subversion | 
  | 
      Commands:$ cvs status…File: baz.c   Status: Needs Patch…$ cvs -n updateM foo.cU bar.c…Explanation:The cvs status command shows whether a file is
      locally modified or out of date, including information about
      working revision and branch info.  A less verbose option is to
      run cvs -n update instead, which shows a compact
      listing of both out-of-date and locally modified files, without
      actually updating the working copy. | 
      Commands:$ svn status -uM     46     foo.cM  *  46     bar.c   *  46     baz.c…Explanation:Shows modified files (M) as well as out-of-date
      files (*).  Contacts repository, but doesn't modify the
      working copy.  To see working revision and branch information,
      run svn info. | 
  - Book References:
- Examine Your Changes
- svn status
 
Scheduling additions or deletions
Schedule a working-copy file or directory to be added or
      removed from the repository.
  | CVS | Subversion | 
  | 
      Commands:$ touch foo.c$ cvs add foo.ccvs server: scheduling file `blah' for additioncvs server: use 'cvs commit' to add this file permanently $ mkdir new-dir$ cvs add new-dirDirectory new-dir added to the repository $ rm bar.c$ cvs rm bar.ccvs remove: scheduling `bar.c' for removalcvs remove: use 'cvs commit' to remove this file permanently $ rm -rf old-dir/*$ cvs rm old-dircvs remove: Removing 3bits…Explanation:Schedules a file or directory for addition or removal
      to/from the repository.  The repository will not be changed
      until the user runs cvs commit, except for the case of
      adding a directory, which immediately changes the repository.
      Also, directories cannot be truly removed from the repository,
      just emptied out.  (cvs update -P will prune empty
      directories from your working copy.) | 
      Commands:$ touch foo.c$ svn add foo.cA     foo.c $ mkdir new-dir$ svn add new-dirA     new-dir $ svn rm bar.cD     bar.c $ svn rm old-dirD     old-dir/file1D     old-dir/file2…Explanation:Schedules a file or directory for addition or removal
      to/from the repository.  The repository will not be changed
      until the user runs svn commit.  The scheduled
      operations are shown as A or D by svn
      status, and svn revert can un-do the scheduling.
      Directories really can be deleted (though as with all deleted
      items, continues to exist in history.) | 
  - Book References:
- Make Changes to Your Working Copy
- svn add
- svn delete
 
Copying and moving
Copy or move/rename a file or directory.
  | CVS | Subversion | 
  | 
      Commands:(not possible.)Explanation:Not possible, unless an administrator directly mucks with
      RCS files in the repository.  (And in that case, no history
      records the act of copying or renaming.) | 
      Commands:$ svn copy foo.c foo2.cA     foo2.c $ svn copy dir dir2A     dir2 $ svn move bar.c baz.cA     baz.cD     bar.c $ svn move dirA dirBA     dirBD     dirA/file1D     dirA/file2…Explanation:The svn copy command schedules a file or directory
      for addition to the repository, recording the "source" of the
      copy.  After committing, svn log on the copied item
      will trace history back through the original copy-source.  The
      svn move command is exactly equivalent to running
      svn copy, followed by an svn delete on the
      copy-source: the result is a new item scheduled for addition
      (with copy-history attached) and the original item scheduled for
      deletion. | 
  - Book References:
- Make Changes to Your Working Copy
- svn copy
- svn move
 
Finding the beginning of a branch
If you're attempting to merge an entire branch into another, you
need to compare the "root" and "tip" of the source branch, and then
merge those differences into a working copy of the target branch.
Obviously the "tip" of the branch can be represented by using the
HEAD keyword.  But how do you find the "birth" revision of
the source branch?
The easiest solution is to run
   $ svn log -v --stop-on-copy source-branch-URL
   …
This command will display every change ever made to the branch, but
--stop-on-copy option will cause the output to stop as soon
as detects a copy operation in the branch's history.  By definition,
then, the very last log entry printed will show the copy being made.
It will look something like:
r9189 | joe | 2004-03-22 10:10:47 -0600 (Mon, 22 Mar 2004) | 1 line
Changed paths:
   A /branches/mybranch (from /trunk:9188)
In this case, you would then know to compare revisions 9189 and
HEAD of the branch in order to perform the merge:
   $ svn merge -r9189:HEAD source-branch-URL target-branch-WC
   …
 
Seeing all of a project's tags
Assuming you've been following a consistent policy for creating
tag-copies, then this is just a matter of running svn ls on a
directory containing your tags.  Typically you would run it on the
/tags directory in your repository, although you're certainly
free to organize this directory in a more complex way, or invent a
different convention altogether.
As an example, you can see all of Subversion's tags by running:
   $ svn ls --verbose http://svn.apache.org/repos/asf/subversion/tags
     …
       7739 kfogel              Nov 13 22:05 0.33.0/
       7796 josander            Nov 18 12:15 0.33.1/
       7932 josander            Dec 03 17:54 0.34.0/
       8045 josander            Dec 19 15:13 0.35.0/
       8063 josander            Dec 20 11:20 0.35.1/
       8282 josander            Jan 13 14:15 0.36.0/
       8512 josander            Jan 24 17:31 0.37.0/
       8810 kfogel              Feb 23 03:44 1.0.0/
     …
 
Seeing the differences between two tags
Just use svn diff in its fully expanded form, which
compares any two URLs:
   $ svn diff tagURL1 tagURL2
   …
 
Seeing logs between two tags
This is a somewhat common practice in CVS, and is doable in Subversion,
but requires a little bit more work.  Assuming that you've made two
tags of /trunk at different points in time, the ultimate goal
here is to run 
   $ svn log -rX:Y trunkURL
…where X and Y are the revisions from which the two tags were
copied.  To discover X and Y, you can use the same technique
described in the previous section ("finding the beginning of a
branch".)  Just use the --stop-on-copy option when logging the
history of each tag.  No commits happen on tag directories, so the
following commands should each produce exactly one log
entry:
   $ svn log -v --stop-on-copy tag1-URL
   r3520 | joe | 2004-03-12 15:28:43 -0600 (Fri, 12 Mar 2004) | 1 line
   …
   $ svn log -v --stop-on-copy tag2-URL
   a
   r4177 | joe | 2004-03-12 15:28:43 -0600 (Fri, 12 Mar 2004) | 1 line
   …
So in this example, the values of X and Y are 3520 and 4177.  Now
you can view all /trunk changes between those two points in time:
   $ svn log -r3520:4177 trunkURL
   …
 
Fixing an incorrect tag
If your tag is a bit off, you can "adjust" it just as people often
do in CVS.  Simply check out a working copy of the tag directory, make
any changes you wish, and commit.
Remember, because branches and tags are directories, they can also
be deleted when they're no longer of any use to your project.  They'll
continue to exist in the repository's history.
 
Creating/using "modules"
Compare CVS Modules vs. svn:externals.