ck_hs_fas — fetch and store key in hash set

       The  ck_hs_fas(3)  function  will  fetch  and store the key specified by the key argument in the hash set
       pointed to by the hs argument. The key specified by key is expected to have the hash value  specified  by
       the hash argument (which was previously generated using the CK_HS_HASH(3) macro).

       If  the  call to ck_hs_fas(3) was successful then the key specified by key was successfully stored in the
       hash set pointed to by hs.  The key must already exist in the hash set, and is replaced by  key  and  the
       previous  value  is stored into the void pointer pointed to by the previous argument. If the key does not
       exist in the hash set then the function will return false and the hash set is unchanged. This function is
       guaranteed to be stable with respect to memory usage.

       Behavior is undefined if key or hs are uninitialized.

       Concurrency Kit (libck, -lck)

       ck_hs_fas — fetch and store key in hash set

       Upon successful completion, ck_hs_fas(3) returns true and otherwise returns false on failure.

ck_hs_init(3), ck_hs_move(3),  ck_hs_destroy(3),  CK_HS_HASH(3),  ck_hs_iterator_init(3),  ck_hs_next(3),
       ck_hs_get(3),   ck_hs_put(3),   ck_hs_put_unique(3),  ck_hs_remove(3),  ck_hs_grow(3),  ck_hs_rebuild(3),
       ck_hs_gc(3), ck_hs_count(3), ck_hs_reset(3), ck_hs_reset_size(3), ck_hs_stat(3)

       Additional information available at http://concurrencykit.org/

                                                  June 20, 2013                                     CK_HS_FAS(3)

#include<ck_hs.h>boolck_hs_fas(ck_hs_t*hs, unsignedlonghash, constvoid*key, void**previous);