1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE /* needed to get the defines */
3 #include <fcntl.h> /* in glibc 2.2 this has the needed
4 values defined */
5 #include <signal.h>
6 #include <stdio.h>
7 #include <unistd.h>
8
9 static volatile int event_fd;
10
handler(int sig,siginfo_t * si,void * data)11 static void handler(int sig, siginfo_t *si, void *data)
12 {
13 event_fd = si->si_fd;
14 }
15
main(void)16 int main(void)
17 {
18 struct sigaction act;
19 int fd;
20
21 act.sa_sigaction = handler;
22 sigemptyset(&act.sa_mask);
23 act.sa_flags = SA_SIGINFO;
24 sigaction(SIGRTMIN + 1, &act, NULL);
25
26 fd = open(".", O_RDONLY);
27 fcntl(fd, F_SETSIG, SIGRTMIN + 1);
28 fcntl(fd, F_NOTIFY, DN_MODIFY|DN_CREATE|DN_MULTISHOT);
29 /* we will now be notified if any of the files
30 in "." is modified or new files are created */
31 while (1) {
32 pause();
33 printf("Got event on fd=%d\n", event_fd);
34 }
35 }
36