bsearch man page

Section 3 - openSUSE 10.2 Man Pages

Other operating system man pages available here

Hopefully, this page is exactly what you are looking for, but if not, you can always find further assistance on Unix/Linux Forum!

BSEARCH(3)                 Linux Programmer's Manual                BSEARCH(3)



NAME
       bsearch - binary search of a sorted array

SYNOPSIS
       #include <stdlib.h>

       void *bsearch(const void *key, const void *base, size_t nmemb,
              size_t size, int (*compar)(const void *, const void *));

DESCRIPTION
       The  bsearch() function searches an array of nmemb objects, the initial
       member of which is pointed to by base, for a member  that  matches  the
       object  pointed  to  by  key.   The size of each member of the array is
       specified by size.

       The contents of the array should be in ascending sorted order according
       to the comparison function referenced by compar.  The compar routine is
       expected to have two arguments which point to the key object and to  an
       array  member,  in  that order, and should return an integer less than,
       equal to, or greater than zero if the  key  object  is  found,  respec-
       tively, to be less than, to match, or be greater than the array member.

RETURN VALUE
       The bsearch() function returns a pointer to a matching  member  of  the
       array,  or  NULL  if no match is found.  If there are multiple elements
       that match the key, the element returned is unspecified.

EXAMPLE
       The example below first sorts an array of  structures  using  qsort(3),
       then retrieves desired elements using bsearch().

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

       struct mi {
            int nr;
            char *name;
       } months[] = {
            { 1, "jan" }, { 2, "feb" }, { 3, "mar" }, { 4, "apr" },
            { 5, "may" }, { 6, "jun" }, { 7, "jul" }, { 8, "aug" },
            { 9, "sep" }, {10, "oct" }, {11, "nov" }, {12, "dec" }
       };

       #define nr_of_months (sizeof(months)/sizeof(months[0]))

       static int compmi(const void *m1, const void *m2) {
            struct mi *mi1 = (struct mi *) m1;
            struct mi *mi2 = (struct mi *) m2;
            return strcmp(mi1->name, mi2->name);
       }

       int main(int argc, char **argv) {
            int i;

            qsort(months, nr_of_months, sizeof(struct mi), compmi);
            for (i = 1; i < argc; i++) {
                 struct mi key, *res;
                 key.name = argv[i];
                 res = bsearch(&key, months, nr_of_months,
                            sizeof(struct mi), compmi);
                 if (res == NULL)
                      printf("'%s': unknown month\n", argv[i]);
                 else
                      printf("%s: month #%d\n", res->name, res->nr);
            }
            return 0;
       }

CONFORMING TO
       SVr4, 4.3BSD, POSIX.1-2001, C99

SEE ALSO
       hsearch(3), lsearch(3), qsort(3), tsearch(3)



                                  2003-11-01                        BSEARCH(3)

Your favourite pages:

No pages logged yet.
Trying to save cookie...

Top 10 most popular pages:

svn man page (6140 hits)
(FreeBSD 6.2)

sqlite3 man page (5592 hits)
(openSUSE 10.2)

adv_cap_autoneg man page (5041 hits)
(Solaris 10 11_06)

CPAN man page (4786 hits)
(Suse Linux 10.1)

ssh man page (4438 hits)
(Suse Linux 10.1)

ssh-socks5-proxy-connect man page (3506 hits)
(Solaris 10 11_06)

signal man page (3363 hits)
(Suse Linux 10.1)

netcat man page (3359 hits)
(Suse Linux 10.1)

pprosetup man page (2874 hits)
(Solaris 10 11_06)

startproc man page (2732 hits)
(Suse Linux 10.1)