lsearch(3C)                                              lsearch(3C)


       NAME
             lsearch, lfind - linear search and update

       SYNOPSIS
             #include <search.h>
             void *lsearch (const void *key, void * base, size_t *nelp,
                 size_t width, int (*compar) (const void *, const void *));
             void *lfind (const void *key, const void *base, size_t *nelp,
                 size_t width, int (*compar)(const void *, const void *));

       DESCRIPTION
             lsearch is a linear search routine generalized from Knuth
             (6.1) Algorithm S.  It returns a pointer into a table
             indicating where data may be found.  If the data does not
             occur, it is added at the end of the table.  key points to the
             data to be sought in the table.  base points to the first
             element in the table.  nelp points to an integer containing
             the current number of elements in the table.  The integer is
             incremented if the data is added to the table.  width is the
             size of an element in bytes.  compar is a pointer to the
             comparison function that the user must supply (strcmp, for
             example).  It is called with two arguments that point to the
             elements being compared.  The function must return zero if the
             elements are equal and non-zero otherwise.

             lfind is the same as lsearch except that if the data is not
             found, it is not added to the table.  Instead, a null pointer
             is returned.

          Return Values
             If the searched-for data is found, both lsearch and lfind
             return a pointer to it.  Otherwise, lfind returns NULL and
             lsearch returns a pointer to the newly added element.

       USAGE
             This program will read in less than TABSIZE strings of length
             less than ELSIZE and store them in a table, eliminating
             duplicates, and then will print each entry.

                   #include <search.h>
                   #include <string.h>
                   #include <stdlib.h>
                   #include <stdio.h>
                   #define TABSIZE 50
                   #define ELSIZE 120
                   main()


                           Copyright 1994 Novell, Inc.               Page 1

      lsearch(3C)                                              lsearch(3C)


                  {
                        char line[ELSIZE];         /* buffer to hold input string */
                        char tab[TABSIZE][ELSIZE]; /* table of strings */
                        size_t nel = 0;            /* number of entries in tab */
                        int i;
                        while (fgets(line, ELSIZE, stdin) != NULL &&
                              nel < TABSIZE)
                              (void) lsearch(line, tab, &nel, ELSIZE, mycmp);
                        for( i = 0; i < nel; i++ )
                              (void)fputs(tab[i], stdout);
                        return 0;
                  }

      REFERENCES
            bsearch(3C), hsearch(3C), string(3C), tsearch(3C)

      NOTICES
            The pointers to the key and the element at the base of the
            table may be pointers to any type.

            The comparison function need not compare every byte, so
            arbitrary data may be contained in the elements in addition to
            the values being compared.

            The value returned should be cast into type pointer-to-
            element.

            Undefined results can occur if there is not enough room in the
            table to add a new item.



















                          Copyright 1994 Novell, Inc.               Page 2