Dynamically Loadable Modules (DLM)

QUESTION: I've been hearing about Dynamically Loadable Modules (DLM), but I can't find any documentation. Where can I learn more?

ANSWER: Dynamically Loadable Modules (DLM) seem to be a well-kept secret. Get a copy of the IDL Reference Guide entitled IDL External Development Guide. This guide was released along with IDL 5.1 and is similar to, but not the same as, a Reference Guide entitled IDL Advanced Development Guide. Be sure you get the correct one. These guides are usually free for the asking.

Although you won't find Dynamically Loadable Modules (or DLM, for that matter) in the index to the Reference Guide, you do have the book you need. Turn to page 242 for additional information.

DLMs are the easiest way to use Linkimage. Their huge advantage is that they are not added to the IDL process until and unless they are required.

If you want to learn more about DLMs, you may want to visit Stein Vidar Hagfors Haugan's web tutorial on the subject. You can find the DLM tutorial at this URL:

   http://folk.uio.no/steinhh/idl/additions.html