1. Change directory

cd $DIRNAME

$DIRNAME can an be absolute path (e.g. /usr/local/) or a relative path (e.g. ../../sbin/ if we want to up 2 level from current directory and then go down to sbin directory).

2. List directory content

ls
ls -l

-l option : use long listing format.

3. Report file system disk space usage

df -h

-h option: print sizes in human readable format.

4. Estimate file space usage

du -sh

-s option: display only a total for each argument.
-h option: print sizes in human readable format.

Subversion helps us to keep track on files. It is very helpful, especially when we are dealing with plain text (not binary). It help us to know: what, when, who, and why someone in our team changed the code. The very nice thing of subversion is that it prevents us from finding that our work has been falsely modified or deleted by unknown people (which is very annoying).

If you are using Windows, TortoiseSVN provides an easy-to-use subversion client which is embedded in your Windows Explorer. If you are using Linux, you can use KDESVN or subversion command line inside terminal. These subversion clients basically implements the same concept.

When using a subversion client, you have to do some basic things like this:

• Checkout. This is a process of retrieving data from subversion server. We need to do this only at the first time, when we didn’t have any data from server. After doing checkout, you will get something called “working copy”, which is a folder containing data from server. Then you can work inside your working copy.
• Status. Subversion client will let you know what modifications (e.g. modify files, delete files, add new files) you have done inside your working copy.
• Commit. If you have changed something inside your working copy and you have done working on it, you may want to put your work to the server. Putting your work to the server is called commit. After you commit, other people in your team can get your work inside their working copy.
• Update. This is a reverse process of commit. It is the way we get updates from other’s people work.
• Log. It will tell you the revision history: when, who, why people have committed, and what files have been committed in the subversion server.

I suggest you to read http://svnbook.red-bean.com/ if you are eager to know more about subversion.