https://svn.boost.org/trac10/ticket/6531 <p> <a href="http://www.boost.org/doc/libs/1_48_0/doc/html/interprocess/synchronization_mechanisms.html#interprocess.synchronization_mechanisms.upgradable_mutexes">http://www.boost.org/doc/libs/1_48_0/doc/html/interprocess/synchronization_mechanisms.html#interprocess.synchronization_mechanisms.upgradable_mutexes</a> </p> <p> quote 1 from </p> <p> Upgradable Mutexes / What's An Upgradable Mutex? / Upgradable lock: </p> <p> (...)If a thread acquires an upgradable lock, other threads <strong>can</strong> acquire a sharable lock.(...) </p> <ul><li>(true) </li></ul><p> quote 2 from </p> <p> Upgradable Mutexes / Upgradable Mutex Operations / Sharable Locking: </p> <p> void lock_sharable() </p> <p> Effects: The calling thread tries to obtain sharable ownership of the mutex, and if another thread has exclusive <strong>or upgradable</strong> ownership of the mutex, <strong>waits until it can</strong> obtain the ownership. </p> <ul><li>(false for upgradable ownership) </li></ul><p> in lock_sharable(), try_lock_sharable(), timed_lock_sharable() etc. </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/6531 Trac 1.4.3 Ion Gaztañaga Sat, 11 Feb 2012 18:21:30 GMT https://svn.boost.org/trac10/ticket/6531#comment:1 https://svn.boost.org/trac10/ticket/6531#comment:1 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">fixed</span> </li> </ul> <p> Thanks for the report. Fixed in revisions 76979 &amp; 76980 in trunk and release branches. </p> Ticket