Open Group Base Specifications Issue 8 (aka POSIX) published

A new version of the POSIX standard has recently been published. This includes a new set of thread functions originally proposed by me so that I could implement them in Glibc.

I proposed these functions so that I could fix the implementation of std::condition_variable::wait_for and std::condition_variable::wait_until to work correctly when the system clock is warped. This can happen particularly at boot time on devices that lack a real time clock. You can learn more about this problem in my earlier blog post and about how it is fixed in GCC 10 and later provided you have Glibc 2.30 or later. I ended up proposing a whole set of functions to fix the problem for mutexes and read-write locks too along with adding new non-standard pthread_clockjoin_np function.

It’s now nearly a decade since I first started trying to fix this problem so it is great to see the new standard version be published. Looking at the search results for pthread_cond_clockwait I didn’t really realise how annoying it would be for people attempting to run binaries compiled against new C libraries with older versions.

Thanks to everyone who reviewed my text and code changes and did the hard work of publishing a new standard.