tst(3) [debian man page]

tst(3)							    InterNetNews Documentation							    tst(3)

NAME

       tst - ternary search trie functions

SYNOPSIS

	   #include <inn/tst.h>

	   struct tst;

	   struct tst *tst_init(int node_line_width);

	   void tst_cleanup(struct tst *tst);

	   int tst_insert(struct tst *tst, const unsigned char *key, void *data, int option, void **exist_ptr);

	   void *tst_search(struct tst *tst, const unsigned char *key);

	   void *tst_delete(struct tst *tst, const unsigned char *key);

DESCRIPTION

       tst_init allocates memory for members of struct tst, and allocates the first node_line_width nodes. A NULL pointer is returned by tst_init
       if any part of the memory allocation fails. On success, a pointer to a struct tst is returned.

       The value for node_line_width must be chosen very carefully. One node is required for every character in the tree. If you choose a value
       that is too small, your application will spend too much time calling malloc(3) and your node space will be too spread out. Too large a
       value is just a waste of space.

       tst_cleanup frees all memory allocated to nodes, internal structures, as well as tst itself.

       tst_insert inserts the string key into the tree. Behavior when a duplicate key is inserted is controlled by option. If key is already in
       the tree then TST_DUPLICATE_KEY is returned, and the data pointer for the existing key is placed in exist_ptr.  If option is set to
       TST_REPLACE then the existing data pointer for the existing key is replaced by data.  Note that the old data pointer will still be placed
       in exist_ptr.

       If a duplicate key is encountered and option is not set to TST_REPLACE then TST_DUPLICATE_KEY is returned. If key is zero length then
       TST_NULL_KEY is returned. A successful insert or replace returns TST_OK. A return value of TST_ERROR indicates that a memory allocation
       error occurred while trying to grow the node free.

       Note that the data argument must never be NULL. If it is, then calls to tst_search will fail for a key that exists because the data value
       was set to NULL, which is what tst_search returns. If you just want a simple existence tree, use the tst pointer as the data pointer.

       tst_search finds the string key in the tree if it exists and returns the data pointer associated with that key.

       If key is not found then NULL is returned, otherwise the data pointer associated with key is returned.

       tst_delete deletes the string key from the tree if it exists and returns the data pointer assocaited with that key.

       If key is not found then NULL is returned, otherwise the data pointer associated with key is returned.

HISTORY

       Converted to POD from Peter A. Friend's ternary search trie documentation by Alex Kiernan <alex.kiernan@thus.net> for InterNetNews 2.4.0.

       $Id: tst.pod 9074 2010-05-31 19:01:32Z iulius $

INN 2.5.3							    2011-06-10								    tst(3)

Check Out this Related Man Page

TSEARCH(3)						   BSD Library Functions Manual 						TSEARCH(3)

NAME

     tsearch, tfind, tdelete, twalk -- manipulate binary search trees

SYNOPSIS

     #include <search.h>

     void *
     tdelete(const void * restrict key, void ** restrict rootp, int (*compar) (const void *, const void *));

     void *
     tfind(const void *key, void * const *rootp, int (*compar) (const void *, const void *));

     void *
     tsearch(const void *key, void **rootp, int (*compar) (const void *, const void *));

     void
     twalk(const void *root, void (*action) (const void *, VISIT, int));

DESCRIPTION

     The tdelete(), tfind(), tsearch(), and twalk() functions manage binary search trees based on algorithms T and D from Knuth (6.2.2).  The com-
     parison function passed in by the user has the same style of return values as strcmp(3).

     The tfind() function searches for the datum matched by the argument key in the binary tree rooted at rootp, returning a pointer to the datum
     if it is found and NULL if it is not.

     The tsearch() function is identical to tfind() except that if no match is found, key is inserted into the tree and a pointer to it is
     returned.	If rootp points to a NULL value a new binary search tree is created.

     The tdelete() function deletes a node from the specified binary search tree and returns a pointer to the parent of the node to be deleted.
     It takes the same arguments as tfind() and tsearch().  If the node to be deleted is the root of the binary search tree, rootp will be
     adjusted.

     The twalk() function walks the binary search tree rooted in root and calls the function action on each node.  The action function is called
     with three arguments: a pointer to the current node, a value from the enum typedef enum { preorder, postorder, endorder, leaf } VISIT; speci-
     fying the traversal type, and a node level (where level zero is the root of the tree).

RETURN VALUES

     The tsearch() function returns NULL if allocation of a new node fails (usually due to a lack of free memory).

     The tfind(), tsearch(), and tdelete() functions return NULL if rootp is NULL or the datum cannot be found.

     The twalk() function returns no value.

SEE ALSO

     bsearch(3), hsearch(3), lsearch(3)

BSD
								   June 15, 1997							       BSD

Linux and UNIX Man Pages

tst(3) [debian man page]

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