inotify监控文件变化

#include <stdio.h>
#include <sys/epoll.h>
#include <sys/inotify.h>

int g_epollFd;
char event_buf[512];

int main(int argc, char *const *argv) {
        int i, ret;
        int fd, wd;
        int nfds;
        int event_pos = 0;
        int event_size = 0;
        struct epoll_event ev,events[5];
        struct inotify_event *inotify_event;

        for (i = 1; i < argc; i++) {
                printf("arg %d is %s\r\n", i, argv[i]);
        }

        g_epollFd = epoll_create(10);
        if (g_epollFd == -1) {
                printf("g_epollFd error\r\n");
                return -1;
        }

        fd = inotify_init();
        if (fd == -1) {
                printf("fd error\r\n");
                return -1;
        }

        printf("EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLET %u %u %u %u\r\n", EPOLLIN, EPOLLERR, EPOLLHUP, EPOLLET);
        printf("IN_CREATE |  IN_DELETE | IN_MODIFY %u %u %u\r\n", IN_CREATE, IN_DELETE, IN_MODIFY);
        wd = inotify_add_watch(fd, argv[1], IN_CREATE |  IN_DELETE | IN_MODIFY);
        if (wd == -1) {
                printf("inotify_add_watch error\r\n");
                return -1;
        }

        ev.data.fd = fd;
        ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLET;

        if (epoll_ctl(g_epollFd, EPOLL_CTL_ADD, fd, &ev) == -1) {
                printf("epoll_ctl error\r\n");
                return -1;
        }

        for ( ; ; ) {
                nfds = epoll_wait(g_epollFd, events, 5, -1);

                for (i = 0; i < nfds; i++) {
                        event_pos = 0;
                        if(events[i].data.fd == fd) {
                                printf("epoll event %d\r\n", events[i].events);
                                ret = read(fd, event_buf, sizeof(event_buf));
                                if(ret < (int)sizeof(struct inotify_event))
                                {
                                        printf("counld not get event!\n");
                                        return -1;
                                }
                                while( ret >= (int)sizeof(struct inotify_event) )
                                {
                                        inotify_event = (struct inotify_event*)(event_buf + event_pos);
                                        printf("inotify_event->len %d\r\n", inotify_event->len);
                                        printf("inotify event %d\r\n", inotify_event->mask);
                                        if(inotify_event->len)
                                        {
                                                if(inotify_event->mask & IN_CREATE)
                                                {
                                                        printf("create file: %s\n", inotify_event->name);
                                                }
                                                else if (inotify_event->mask & IN_DELETE)
                                                {
                                                        printf("delete file: %s\n", inotify_event->name);
                                                }
                                                else
                                                {
                                                        printf("modify file: %s\n", inotify_event->name);
                                                }
                                        }

                                        event_size = sizeof(struct inotify_event) + inotify_event->len;
                                        ret -= event_size;
                                        event_pos += event_size;
                                }

                        }
                }
        }

        (void)inotify_rm_watch(fd, wd);
        close(fd);
        close(g_epollFd);
}

gcc main.c -o main
./main /home/

另起控制台 /home/ 下增删改文件