SI_USER
if (sig != SIGUSR1 || sinfo->si_code != SI_USER ||
case SI_USER:
if (si.si_code == SI_USER || si.si_code == SI_QUEUE) {
if (si->si_code == SI_USER || si->si_code == SI_QUEUE) {
info.si_code = SI_USER;
v.sicode = SI_USER;
v.sicode = SI_USER;