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1220. What does condition_variable wait on?

Section: 32.7 [thread.condition] Status: C++11 Submitter: Jeffrey Yasskin Opened: 2009-09-30 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

"Class condition_variable provides a condition variable that can only wait on an object of type unique_lock" should say "...object of type unique_lock<mutex>"

[ 2009-11-06 Howard adds: ]

Moved to Tentatively Ready after 5 positive votes on c++std-lib.

Proposed resolution:

Change 32.7 [thread.condition], p1:

Condition variables provide synchronization primitives used to block a thread until notified by some other thread that some condition is met or until a system time is reached. Class condition_variable provides a condition variable that can only wait on an object of type unique_lock<mutex>, allowing maximum efficiency on some platforms. Class condition_variable_any provides a general condition variable that can wait on objects of user-supplied lock types.