Updating ports collection
A Mac Ports port is a set of specifications contained in a Portfile that defines an application, its characteristics, and any files or special instructions required to install it.
You can also get the command line tools from the Apple developer website.
Xcode 4.3 and later do not automatically install the command line tools, but Mac Ports requires them.
There are two options for downloading it: Both are available from the Apple developer website.
You may also be able to install Xcode 3.2 from your Mac OS X 10.6 DVD and then run Software Update to get the latest version.
The selfupdate command installs the latest ports tree, and updates Mac Ports base to the latest released version.