Bit Mask 업무 실사용 예시

@ PostgreSQL Server Extension

Status Code를 bit mask하여 컨디션을 줄 때도 or(

)로 주고, 체크할 때도 and(&)로 쉽게 가능.

code

/* Returns bit mask indicating which condition(s) caused the wake-up. */
int events = WaitLatch(MyLatch,
                    WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH,
                    1000L,
                    PG_WAIT_EXTENSION);
ResetLatch(MyLatch);
if (events & WL_POSTMASTER_DEATH)
    elog(FATAL, "unexpected Postmaster dead");