OpenIndiana uses the same package management system as Oracle Solaris 11, and Oracle is thus far continuing Sun's practice of providing well written manuals:
http://download.oracle.com/docs/cd/E19963-01/html/820-6572/index.html
The command line package manager is 'pkg'
Set a remote repository:
sudo pfexec pkg set-publisher -O http://pkg.openindiana.org/dev openindiana.org
Search for a package:
pkg search -pr git
Install a package:
sudo pkg install git
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