Multithreading-reader/writer Locks in C + +

You have need to Note this:only 1 single thread can acquire a upgrade_lock at one time.

Others is very straightforward.

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1800 information was more or less correct, but there was a few issues I wanted to correct. Boost::shared_mutex _access;voidReader () {Boost::shared_lock< Boost::shared_mutex >Lock(_access); //Do work here , without anyone have exclusive access}voidConditional_writer () {Boost::upgrade_lock< Boost::shared_mutex >Lock(_access); //Do work here , without anyone have exclusive access if(something) {Boost::upgrade_to_unique_lock< Boost::shared_mutex > Uniquelock (Lock); //Do exclusive access } //Do more work here , without anyone have exclusive access}voidUnconditional_writer () {Boost::unique_lock< Boost::shared_mutex >Lock(_access); //Do work here , with exclusive access} Also Note, unlike a shared_lock, only a single thread can acquire an upgrade_lock at one time, even when it isn ' t upgraded (which I thought was awkward when I ran to it). So, if all your readers is conditional writers, you need to find another solution.

Test Code:

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Multithreading-reader/writer Locks in C + +