bsearch(3)

bsearch3

Binary search of a sorted table

Usage

#include <stdlib.h>

void *

bsearch(const void *key, const void *base, size_t nel, size_t width, int (*compar) (const void *, const void *)); #ifdef UNIFDEF_BLOCKS

void *

bsearch_b(const void *key, const void *base, size_t nel, size_t width, int (^compar) (const void *, const void *)); #endif

Overview

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

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. It should return an integer which is less than, equal to, or greater than zero if the key object is found, respectively, to be less than, to match, or be greater than the array member. #ifdef UNIFDEF_BLOCKS

The bsearch_b() function is like bsearch() except the callback compar is a block pointer instead of a function pointer. #endif

Return values

The bsearch() #ifdef UNIFDEF_BLOCKS and bsearch_b() functions #else function #endif returns a pointer to a matching member of the array, or a null pointer if no match is found. If two members compare as equal, which member is matched is unspecified.

Releases

163 releases since Mac OS X 10.0; the text changed 4 times.

  1. 10.0–10.1.5
  2. 10.2–10.4.11
  3. 10.5–10.5.8
  4. 10.6–10.6.8
  5. 10.7–26.5

Standards

The bsearch() function conforms to ISO/IEC 9899:1990 (“ISO C90”).

From Libc 1752.120.2 in macOS 26.5. Parsed by carta from the page's mdoc source.