How to “unversion” a file in either svn and/or git

Question

It happens to me all the time. I accidentally version a file, I do not want to be versioned (i.e. developer/machine specific config-files).

If I commit this file, I

Answer 1

Look up svn:ignore and .gitignore - these features allow you to have extra files in your checkout that are ignored by your RCS (when doing a "status" operation or whatever).

For machine-specific config files, a good option is to check in a file named with an extra ".sample" extension, ie. config.xml.sample. Individual developers would make a copy of this file in config.xml and tweak it for their system. With svn:ignore or .gitignore you can ensure that the unversioned config.xml file doesn't show up as dirty all the time.

In response to your edit: If you remove the file from the repository now, then your developers will get a conflict next time they do an update (assuming they have all changed the file for their system). They won't lose their local changes, they will be recoverable from somewhere. If they happen not to have made any local changes, then their config file will vanish but they can just re-get the previous one out of source control and use that.