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From: Bonita Montero <Bonita.Montero@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Futexes ain't fast
Date: Fri, 30 Aug 2024 18:47:51 +0200
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In-Reply-To: <vaqkng$3vj5$2@dont-email.me>

Am 29.08.2024 um 22:12 schrieb Chris M. Thomasson:
> On 8/29/2024 7:30 AM, Bonita Montero wrote:
>> This is by far the fastest code:
>>
>> #if defined(_WIN32)
>>      HANDLE hSem = CreateSemaphoreA( nullptr, 0, 0x7FFFFFFF, nullptr );
>>      auto acquire = [&] { WaitForSingleObject( hSem, INFINITE ); };
>>      auto release = [&] { ReleaseSemaphore( hSem, 1, nullptr ); };
>> #elif defined(__unix__)
>>      sem_t sem;
>>      sem_init( &sem, 0, 0 );
>>      auto acquire = [&] { while( sem_wait( &sem ) == EINTR ); };
> [...]
> 
> Nice touch with the EINTR. I have seen a lot of code that misses this 
> aspect... Yikes!

Signals are really sick.