wn_slleunlink3

Usage

Overview

This package defines a singly linked list type called "wn_sll". Routines and macros operate on lists and elements of lists.

The declaration

wn_sll ll;

declares a list element, which is also a list. The fragment

ll->next

refers to the next linked list element. The fragment

ll->contents

is a pointer associated with the linked list element.

wn_mksll allocates a wn_sll from the current memory group. ll->next and ll->contents are NULL.

wn_sllins inserts e into list list by allocating a list element (from the current memory group), setting its contents to e, and chaining it to the front of list.

wn_slleins chains el to the front of list.

wn_slldel searches list until it finds a list element with contents == e. This element is deleted from the list and freed into the current memory group.

wn_slledel deletes the list element *pel from its containing list by setting "*pel = (*pel)->next;". Then the list element is freed into the current memory group.

wn_slleunlink deletes the list element *pel from its containing list by setting "*pel = (*pel)->next;".

wn_sllindex places the contents of the \fIindex\fPth element of list into contents. Unreasonable values of index are NOT trapped.

wn_slleindex places the \fIindex\fPth element of list into el. Unreasonable values of index are NOT trapped.

wn_sllrev reverses the order of list. Useful because wn_sllins leaves the list reversed from the order of insertion.

wn_sllcpy places a memory-allocated copy of in into out. The memory is allocated from the current memory group.

wn_sllcat concatonates in to the end of out, preserving the order of both. No new memory is allocated.

wn_sllins_sll chains the list in to the front of out.

wn_sllend places the last->next pointer of list into pend.

wn_slllast gets the last element of list.

wn_sllempty returns TRUE iff list is empty.

wn_sllcount returns the number of entries in list.