Linux

int fd = socket(AF_INET, SOCK_STREAM, IPPROTO_IP);// 将 fd 设置成非阻塞fcntl(fd, F_SETFL, fcntl(fd, F_GETFL)| O_NONBLOCK);connect(...);

Windows

SOCKET sock = socket(AF_INET, SOCK_STREAM, IPPROTO_IP);// 将 sock 设置成非阻塞unsigned long mode = 1;ioctlsocket(sock, FIONBIO, (unsigned long *)&mode);connect(...);

参考资料

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