Loading drivers takes time - it is expensive in terms of application performance. For this reason, ISIS is designed to allow you to keep drivers loaded yet use them in different pipes. You can load all of the drivers you are likely to need when you start your application, and then link and unlink them as they are needed in different pipes. Don't forget to initialize each driver before linking it. And, if the driver requires initialization parameters, it must be initialized whenever you want to change these parameters. You do not have to reinitialize the driver if it was unlinked from one pipe and linked to another pipe using the same parameters. Unload the drivers only when exiting from the application.

You can use IG_ISIS_drv_load_init_pipe() to load and initialize individual drivers, and then use IG_ISIS_drv_link() to link them later.