HP-UX Reference (11i v2 04/09) - 3 Library Functions N-Z (vol 7)

tsearch(3C) tsearch(3C)

/* This routine prints out a node, the first time

twalk encounters it. */

void

print_node(element, order, level)

void *element;

VISIT order;

int level;

{

if (order == preorder || order == leaf)

{

(void) printf("string = %20s, length = %d\n",

(*(struct element **) element)->string,

(*(struct element **) element)->length);

}

RETURN VALUE

A NULL pointer is returned by tsearch() if there is not enough space available to create a new node.

NULL pointer is returned by tsearch()

, tfind(), and tdelete() if rootp is NULL on entry.

If the datum is found, both

tsearch() and tfind() return a pointer to it. If not,

tfind() returns

NULL, and tsearch() returns a pointer to the inserted item.

WARNINGS

The root argument to

twalk() is one level of indirection less than the rootp arguments to tsearch()

and tdelete().

Two nomenclatures are used to refer to the order in which tree nodes are visited.

tsearch() uses

preorder, postorder and endorder to respectively refer to visiting a node before any of its children, after

its left child and before its right and after both its children. The alternate nomenclature uses preorder,

inorder, and postorder to refer to the same visits, which could result in some confusion over the meaning

of postorder. If the calling function alters the pointer to the root, results are unpredictable.