SE_READER
pp->p_selock += SE_READER;
pp->p_selock = old + SE_READER;
pp->p_selock += SE_READER;
if ((old & ~SE_EWANTED) == SE_READER) {
pp->p_selock = old & ~SE_READER;
} else if ((old & ~SE_EWANTED) > SE_READER) {
pp->p_selock = old - SE_READER;
if ((old & ~SE_EWANTED) == SE_READER) {
pp->p_selock = old & ~SE_READER;
} else if ((old & ~SE_EWANTED) > SE_READER) {
pp->p_selock = old - SE_READER;
if (pp->p_selock == SE_READER) {
pp->p_selock = SE_READER | excl_waiting;