> Date: Sun, 7 Jan 2024 18:59:09 -0600
> From: Scott Cheloha <scottcheloha@gmail.com>
> 
> All values of tv_sec are valid for absolute timeouts.
> 
> ok?

I think that if we allow "negative" absolute times, the code that
checks if the time has passed in _twait() may fail due to integer
wraps?

> Index: rthread_cond.c
> ===================================================================
> RCS file: /cvs/src/lib/libc/thread/rthread_cond.c,v
> diff -u -p -r1.5 rthread_cond.c
> --- rthread_cond.c	29 Jan 2019 17:40:26 -0000	1.5
> +++ rthread_cond.c	8 Jan 2024 00:55:09 -0000
> @@ -142,8 +142,7 @@ pthread_cond_timedwait(pthread_cond_t *c
>  	}
>  
>  	cond = *condp;
> -	if (abs == NULL || abs->tv_sec < 0 || abs->tv_nsec < 0 ||
> -	    abs->tv_nsec >= 1000000000)
> +	if (abs == NULL || abs->tv_nsec < 0 || abs->tv_nsec >= 1000000000)
>  		return (EINVAL);
>  
>  	return (_rthread_cond_timedwait(cond, mutexp, abs));
> Index: rthread_sync.c
> ===================================================================
> RCS file: /cvs/src/lib/libc/thread/rthread_sync.c,v
> diff -u -p -r1.5 rthread_sync.c
> --- rthread_sync.c	24 Apr 2018 16:28:42 -0000	1.5
> +++ rthread_sync.c	8 Jan 2024 00:55:09 -0000
> @@ -317,7 +317,7 @@ pthread_cond_timedwait(pthread_cond_t *c
>  			abort();
>  	}
>  
> -	if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
> +	if (abstime == NULL || abstime->tv_nsec < 0 ||
>  	    abstime->tv_nsec >= 1000000000)
>  		return (EINVAL);
>  
> 
>