Return address of a mutex associated the specified streambuf object (address). The behavior is undefined unless streambuf is not null and points to basic_streambuf<...> object.
streambuf
basic_streambuf<...>
Declared in <bslstl_syncbuf.h>
<bslstl_syncbuf.h>
static SyncBuf_Mutex* get(void* streambuf) noexcept;