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From: "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Futexes ain't fast
Date: Fri, 30 Aug 2024 12:43:06 -0700
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In-Reply-To: <vast3j$imrm$1@raubtier-asyl.eternal-september.org>

On 8/30/2024 9:47 AM, Bonita Montero wrote:
> 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.

Well, at least your code handles the condition. :^)