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lfind()                  Linear Search for Key

 #include   <search.h>                   Required for declarations only

 char       *lfind(key,base,num,width,compare);
 char       *key;                        Search key
 char       *base;                       Pointer to base of search data
 unsigned   *num, width;                 Number and width of elements
 int        (*compare)();                Pointer to compare function

    lfind() performs a linear search of a table of information. (Compare
    this to bsearch(), which performs a binary search.)  The table is an
    array of '*num' elements, each element being 'width' in size.  'base'
    is a pointer to the base of the array to be searched, and 'key' is
    the item being sought.  'compare' points to a user-supplied routine
    that compares two elements and returns a value based on the
    comparison. 'compare' returns one of the following values:

                  0           'element1' is identical to 'element2'

              not 0           'element1' and 'element2' are different

    Returns:    A pointer to the first occurrence of 'key' in the array
                pointed to by 'base'.  NULL is returned if 'key' is not
                found.

      Notes:    lfind() will make repeated calls to the 'compare' routine
                during the search.  On each call to 'compare', 'key' will
                be compared with one of the elements of 'base'.

                lfind() does not require the array to be sorted (as
                bsearch() does).

                lsearch() operates similarly to lfind(), but lsearch()
                adds 'key' to the end of the list if it is not found;
                lfind() does not.

  -------------------------------- Example ---------------------------------

    The following statements search an array for a value and print out an
    appropriate message.

        #include <search.h>
        #include <stdio.h>
        #include <string.h>

        int vals[] = {10,95,30,75,54,62,15,28,88,100};
        int num = 10;
        int key = 62;
        int *found;
        int cmp();

        main()
        {
            found = (int *)lfind(&key,vals,&num,sizeof(int),cmp);
            if (found)
               printf("%d already in table\n",key);
            else
                printf("%d not found\n",key);
        }

      int cmp(n1,n2)
      int *n1;
      int *n2;
      {
          return(*n1 - *n2);
      }

See Also: bsearch() lsearch() qsort()

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