Initialize pidfd to an invalid descriptor, to fail gracefully on
those kernels that do not implement CLONE_PIDFD and leave pidfd
unchanged.
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Christian Brauner <christian@brauner.io>
int main(int argc, char *argv[])
{
- int pidfd = 0, ret = EXIT_FAILURE;
+ int pidfd = -1, ret = EXIT_FAILURE;
char buf[4096] = { 0 };
pid_t pid;
int procfd, statusfd;
pid = pidfd_clone(CLONE_PIDFD, &pidfd);
if (pid < 0)
- exit(ret);
+ err(ret, "CLONE_PIDFD");
+ if (pidfd == -1) {
+ warnx("CLONE_PIDFD is not supported by the kernel");
+ goto out;
+ }
procfd = pidfd_metadata_fd(pid, pidfd);
close(pidfd);