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Insert string into a $list

Note: Many $functions have been deprecated in favor of Object Oriented methods. The OO equivalent for the $ListIns_Lstr function is Insert.

This function inserts longstring data into a $list. Generally, this $list would have been created with the $ListNew function.

The $ListIns_Lstr function accepts three arguments and returns a numeric result. It is a callable $function.

The first argument is a $list identifier. This is a required argument.

The second argument is the item number before which the longstring is to be inserted. If this argument is equal to the number of items in the $list plus one, the longstring is added to the end of the $list and so is, in this case, identical to a $ListAdd_Lstr Because the string is inserted before the indicated item number, this item number is also the item number of the new $list item after $ListIns_Lstr returns. This is a required argument.

The third argument is a longstring that is to be inserted into the $list. This is a required argument.


[%RESULT =] $ListIns_Lstr(list_id, item_num, longstring)

%result is set either to the number of items in the indicated $list after the string has been inserted into the $list, or to a negative number if an error has occurred.

Error codes

-3 - No room to add item (if LISTFC $SirParm parameter not set) All other errors result in request cancellation

Usage notes

  • $ListIns_Lstr works almost exactly like $ListIns except:
    • It accepts a LONGSTRING input. $ListIns_Lstr can be used with regular strings as well to pick up automatic request cancellation on programming errors.
    • It cancels the request on any errors such as invalid $list identifier or invalid $list item number.
    • It does not have an item length argument (argument 4 in $ListIns).
  • A $ListIns_Lstr can result in the splitting of a $list leaf page. Once a leaf page is split, it will not be merged back together, even if subsequent $LISTREMs makes this possible. Because of this, heavy use of $ListIns_Lstr and $ListRem can result in "sparse&CQ. $lists which place an unnecessary burden on the buffer pool and CCATEMP. To make matters worse, $ListCpy does a page-for-page copy of a $list so does not result in any compression of the resultant $list. $List compression can be done using the $List_Copy_Items function.

Products authorizing $ListIns_Lstr