#include <sys/poll.h>int poll(struct pollfd *ufds, unsigned int nfds, int timeout);struct pollfd{int fd; /* 想查询的文件描述符. */short int events; /* fd 上,我们感兴趣的事件*/short int revents; /* Types of events that actually occurred. */};请问第二个参数unsigned int nfds的含义,它传递什么信息?
參考答案:ufds 指向 struct pollfd 数组
nfds 指定 pollfd 数组元素的个数,也就是要监测几个 pollfd