bsearch - binary search of a sorted array.
void *bsearch(const void *key, const void *base, size_t nmemb
size_t size, int (*compar))(const void *, const void *));
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 argu-
ments 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
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.
SVID 3, BSD 4.3, ISO 9899