Waits for one or more object to enter a signaled state.

Parameters

Count - the number of handles passed in the Handles parameter, up to MAXIMUM_WAIT_OBJECTS (64).
Handles - a pointer to an array of handles. Each handle must grant SYNCHRONIZE access.
WaitType - the type of wait to perform, either WaitAll or WaitAny.
Alertable - determines whether the wait should be altertable. This allows external triggers (such as APCs or calls to NtAlertThread) to interrupt wait prematurely.
Timeout - an optional pointer to a variable that stores the wait internal. A negative value indicates relative timeout for the specified number of 100-nanosecond intervals. To wait a specific number of milliseconds, multiply them by -10,000. Positive values indicate an absolute time. NULL indicates an infinite timeout.

Notable return values

STATUS_WAIT_0..STATUS_WAIT_63 - the thread woke due to the n'th object being signaled.
STATUS_ABANDONED_WAIT_0..STATUS_ABANDONED_WAIT_63 - the thread woke due to the n'th passed mutex becoming abandoned.
STATUS_TIMEOUT - the thread woke due to the timeout.
STATUS_USER_APC - the wait was interrupted by an APC.
STATUS_ALERTED - the wait was interrupted by a call to NtAlertThread.

Despite the name, NtAlertThreadByThreadId is unrelated to alertable waits and cannot interrupt them.