iphone设置非阻塞模式socket两种方法

/* set socket to non-blocking i/o */
sts = ioctl(ccp->main_sock, FIONBIO, (char *)&one);
if (sts)
{
setproderr(PE_TCPERROR, GEL_FATAL);
sprintf(line,"ioctl (main) failed - %s",strerror(errno));
tcpabort();
}

/* Set socket to non-blocking */
if ((flags = fcntl(sock_descriptor, F_GETFL, 0)) < 0)
{
/* Handle error */
}

if (fcntl(socket_descriptor, F_SETFL, flags | O_NONBLOCK) < 0)
{
/* Handle error */
}
/* Set socket to blocking */
if ((flags = fcntl(sock_descriptor, F_GETFL, 0)) < 0)
{
/* Handle error */
}

if (fcntl(socket_descriptor, F_SETFL, flags & (~O_NONBLOCK)) < 0)
{
/* Handle error */
}