struct _mem {
struct _mem *next;
int size; /* size of individual elements in bytes */
int blkf; /* blocking factor */
int bsize; /* block size */
char *block; /* block */
int cnt; /* count of free elem in block */
char *freelist; /* free list */
int totelem; /* total number elements we have */
int freecnt; /* number of times mem_free was called */
};