#include <stdlib.h>

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


Function searches an array of nitems 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 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. 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.

Return value

Functions 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.