Monodevelop: Debug a process that I didn't launch myself

I'm writing a .dll using Monodevelop on Linux that is run by an application, and I have no control over how or when my code is called, but I would like to debug that DLL.

How can I make Monodevelop's debugger attach to that DLL when a chosen method is run in the DLL ?

Alternatively, I thought about starting the debugger from the code itself (i.e. "from now on, please debug me").

The DLL I'm writing contains a xbuild task that throws and obscure exception when run using xbuild (but the code runs fine if I call it from main), so if there's any way to debug custom xbuild tasks, I'm interested in that too.

Solution

Open your library project options
On left side go to Build->Output
Output path: set to path where external application will load your dll
On left side go to Run->Custom Commands
In dropdown box with text (Select a project operation) change to "Execute"
In Command textbox set to external executable that loads your dll

Now you can right click on your library project in SoltuionPad and set "Set As Startup Project"