ld = openat(repo->dfd, "lock", O_CREAT|O_TRUNC|O_WRONLY, 00644);
if (ld == -1) {
pkg_emit_errno("plop", "plop");
pkg_emit_error("plop, %d\n", repo->dfd);
pkg_emit_errno("openat", "lock");
}
if (flock(ld, LOCK_EX|LOCK_NB) == -1) {
/* lock blocking anyway to let the other end finish */