[delbel@localhost t]$ mcs two.cs  -target:library
[delbel@localhost t]$ mcs main.cs
main.cs(9,3): error CS0246: The type or namespace name `Two' could not be found. Are you missing a using directive or an assembl
?
Compilation failed: 1 error(s), 0 warnings
[delbel@localhost t]$ vi two.cs 
[delbel@localhost t]$ mcs main.cs -r:test
error CS0006: Cannot find assembly `test'
Log: 

Compilation failed: 1 error(s), 0 warnings
[delbel@localhost t]$ mcs main.cs -r:test -lib:two.dll 
error CS0006: Cannot find assembly `test'
Log: 

Compilation failed: 1 error(s), 0 warnings
[delbel@localhost t]$ mcs main.cs -r:test -lib:two.dll 
[delbel@localhost t]$ vi two.cs 
[delbel@localhost t]$ cat main.cs
using System;


namespace test {

        class MainRuner 
        {

                Two t;

                static int Main ( string [] args )
                {
                        t = new Two();
                        return 1;
                }

        }
}

[delbel@localhost t]$ cat two.cs
using System;


namespace test {

        class Two 
        {

                public string bob;

        }
}

[delbel@localhost t]$