Have you seen this message lately ?

csvn: Commit failed (details follow):
svn: Could not use external editor to fetch log message; consider setting the $SVN_EDITOR environment variable or using the --message (-m) or --file (-F) options
svn: None of the environment variables SVN_EDITOR, VISUAL or EDITOR is set, and no 'editor-cmd' run-time configuration option was found

Here is how to export SVN_EDITOR variable.

Feel free to change the editor to pico, nano etc.

echo export SVN_EDITOR=vi >> ~/.bash_profile

Logout and then Login again to *see* the change.
By *see* I mean that you have to do execute the following command and the editor of your choice should be run for you:

svn ci