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Linked List Utilities

This section shows some examples how the linked list can be used to make returning a list of simple data easier than using a userspace.

List File Members

This IBM i API - QUSLMBR - uses a userspace to return the data to the caller. The creation and handling of a userspace is sometimes rather cumbersome. Using a linked list for just returning the names of the file members gives the caller some advantages:

  • checking if file has members using list_isEmpty
  • checking if file has a specific member using list_indexOf or list_contains
  • getting the number of members using list_size
  • iterating through all members using list_getNext

List Record Formats

This IBM i API - QUSLRCD - uses a userspace to return the data to the caller. The creation and handling of a userspace is sometimes rather cumbersome. Using a linked list for just returning the names of the record formats is a lot easier than working with userspaces.

List Objects

This procedure is a convience procedure for the IBM i API QUSLOBJ. It accepts the same parameters for library, object name and object type. It also has the same restrictions.