MAX_TCP_SIZE
char buf[MAX_TCP_SIZE], buf2[MAX_TCP_SIZE];
bzero(buf2, MAX_TCP_SIZE);
if (recv(s, buf2, MAX_TCP_SIZE, 0) == -1) {
(void) memset(buf, 0, MAX_TCP_SIZE);
#define BUFLEN_TCP(x, y) (MAX_TCP_SIZE-(x-y))