In addition to the predefined directory, GILDAS_RUN:, another directory GILDAS_LOCAL: is also searched for tasks by commands VECTORRUN and VECTORSUBMIT. This area is searched before GILDAS_RUN:. If the required task is found here, the initialisation, checker and help files should also be present in the same directory. This feature allows to have experimental or user-private tasks.
Although the tasks are supposed to be non-interactive programs spawned or submitted from a main program, interactive use is possible for debugging purpose. If activated interactively, a task will ask one question for each parameter, specifying the parameter type, the parameter name, and the parameter dimension. No more information will be available. The initialization and checker file are not needed for this.
Moreover since all algorithms can be standard subroutines due to the use of virtual memory, the GILDAS interface can be done easily after debugging the algorithm.