How to monitor two paths at the same time using the inotify instance?

Question

In these two functions, I am using inotify instance to monitor the paths and I want to monitor two paths at the same time but after giving the locations of the source and destination, the program gives me a message that both locations are being monitored but this time the inotifyFunc that I call, does not work and the program closes. I don't why?

Although I put while(1) loop above read(monitor.fd, monitor.buffer, BUFFER_LEN); also but it had a problem that whenever I enter the source path, it stops there and didn't ask me the destination path. That's why I remove the while(1).

Is there any other solution to it?

void inotifyFunc(char *path, uint32_t *maskPtr)
{
    int i = 0;
    monitor.fd = inotify_init();
    if(fcntl(monitor.fd, F_SETFL, O_NONBLOCK)){
       perror("inotify not initialized: ");
       exit(0);
    }

    monitor.wd = inotify_add_watch(monitor.fd, path, *maskPtr);
    if(monitor.wd < 0){
        perror("Sorry");
        exit(1);
    }

    monitor.length = read(monitor.fd, monitor.buffer, BUFFER_LEN);
    while(i<monitor.length){
        struct inotify_event *event = (struct inotify_event *)&monitor.buffer[i];
        if(event->len){
            if(event->mask & *maskPtr){
                if(event->mask & IN_ISDIR){
                    printf("Directory is created\n");
                    break;
                }
                else{
                   printf("File is created\n");
                   break;
                }
            }
        }
        i+= EVENT_SIZE + event->len;
    }
}

void monitoringSystem(char *pathname1, char *pathname2){
    monitor.mask[0] = ENOENT;
    monitor.mask[1] = IN_CREATE;

    printf("Choose the source path: ");
    scanf("%s", pathname1);
    inotifyFunc(pathname1, &monitor.mask[0]);

    printf("Choose the destination path: ");
    scanf("%s", pathname2);
    inotifyFunc(pathname2, &monitor.mask[0]);

    printf("\nBoth locations are being monitored\n");
    inotifyFunc(pathname1, &monitor.mask[1]);
    inotifyFunc(pathname2, &monitor.mask[1]);
}

score 1 · Answer 1 · answered Jan 03 '21 at 18:20

This looks to be more of a scanf than inotify issue:

    printf("Choose the source path: ");
    scanf("%s", pathname1);
    inotifyFunc(pathname1, &monitor.mask[0]);

In this case scanf("%s", ...) does not consume the newline - there is much more discussion at The scanf function, the specifer %s and the new line

Generally, you would do: scanf("%s\n", pathname1) and the same for scanf("%s\n",pathname2)

How to monitor two paths at the same time using the inotify instance?

1 Answers1