selftests/filesystems/dnotify_test.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #define _GNU_SOURCE /* needed to get the defines */
0003 #include <fcntl.h>  /* in glibc 2.2 this has the needed
0004                    values defined */
0005 #include <signal.h>
0006 #include <stdio.h>
0007 #include <unistd.h>
0008
0009 static volatile int event_fd;
0010
0011 static void handler(int sig, siginfo_t *si, void *data)
0012 {
0013     event_fd = si->si_fd;
0014 }
0015
0016 int main(void)
0017 {
0018     struct sigaction act;
0019     int fd;
0020
0021     act.sa_sigaction = handler;
0022     sigemptyset(&act.sa_mask);
0023     act.sa_flags = SA_SIGINFO;
0024     sigaction(SIGRTMIN + 1, &act, NULL);
0025
0026     fd = open(".", O_RDONLY);
0027     fcntl(fd, F_SETSIG, SIGRTMIN + 1);
0028     fcntl(fd, F_NOTIFY, DN_MODIFY|DN_CREATE|DN_MULTISHOT);
0029     /* we will now be notified if any of the files
0030        in "." is modified or new files are created */
0031     while (1) {
0032         pause();
0033         printf("Got event on fd=%d\n", event_fd);
0034     }
0035 }