LSEARCH - linear search and update table.

(Compatible with UNIX System V C)

Usage:

#include <stdio.h>
#include <search.h>
char *lsearch();
ptr = lsearch( key, table, tsize_p, keysize, compar);

Where:

char *key;: points to the key you are searching for. This can actually be any type of information, but the pointer must be cast into (char *). If this key is not found in the table, it will be added to the end of the table.
char *table;: points to the beginning of a table that contains information to search. This need not be sorted in any order. It should have enough space to hold a new key, in the event that the desired key is not found in the existing table.
unsigned int *tsize_p;: points to an unsigned integer that gives the number of elements in the table. If the desired key cannot be found in the table and is therefore added to the end of the table, the unsigned integer will be incremented to reflect that the table now has one more element.
int keysize;: is equal to "sizeof(*key)", i.e. the size (in bytes) of the key you are searching for.
int (*compar)(char *,char *);: is a pointer to a user-defined function that determines whether or not two keys are equal. This function should take two (char *) arguments; one will point to the key you are looking for and the other will point to a key in the table. The function should return a zero if the two keys are equal, and a non-zero value otherwise.
char *ptr;: points to a table element that matches "key". If no match was found in the original table, this will point to the new key where it was added at the end of the table.

Description:

"lsearch" performs a linear search through the elements of a table. It uses the user-supplied "compar" function to compare elements in the table. If the desired key is not found in the table, the search key is added to the end of the table.

Note that "compar" does not have to do a byte-by-byte comparison between the key and the table elements. For example, the table may be an array of C structures and "compar" may only look at a particular field when comparing two structures. In this case, the original search key might just be a dummy, with only the significant field filled in.

LSEARCH - linear search and update table.

Usage:

Where:

Description:

See Also: