Is Windows' AcquireSRWLockExclusive recursive?

Question

I need to use read-write lock, but I would also like to be sure that the lock is recursive in both read and write mode, so that calling function that uses it on the same thread doesn't lock.

I found nothing on MSDN docs. Maybe it's hidden somewhere and I didn't find it?

This is clearly documented on the top page of the MSDN documentation. — David Heffernan, Aug 23 '19 at 12:02

score 2 · Accepted Answer · answered Aug 23 '19 at 09:41

2

SRWLocks are not recursive, from the docs:

An SRW lock is the size of a pointer. The advantage is that it is fast to update the lock state. The disadvantage is that very little state information can be stored, so SRW locks cannot be acquired recursively. In addition, a thread that owns an SRW lock in shared mode cannot upgrade its ownership of the lock to exclusive mode.

answered Aug 23 '19 at 09:41

user7860670

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Thanks. The second part is really sad, I wanted to be able to upgrade the lock. That's like 70% of how I ever used RW locks in other libraries. – Tomáš Zato Aug 23 '19 at 09:43

Is Windows' AcquireSRWLockExclusive recursive?

1 Answers1