IEEE 1003.1-2001

This page helps rank how FreeBSD currently functions with certain opensource/UNIX standards, such as ISO C, POSIX, XSI, etc.

CLOCK_UPTIME .. CLOCK_SECOND	FreeBSD specific clocks/timers aren't properly hidden under __BSD_VISIBLE.
_POSIX_CPUTIME, et all	Not implemented, despite the fact that _POSIX_THREAD_CPUTIME is implemented. Gross oversight?
Incorrect includes	Some headers are including time.h and others are including sys/time.h by accident which has resulted in improper breakage in the sourcebase, based on the requirements in the stated in the FreeBSD and OpenGroup manpages.

SCHED_SPORADIC	not implemented
struct sched_param	not implemented

realpath	non-conformant pieces ; see [3]

_SC_TIMERS / _SC_TIMER_MAX	value doesn't take into account offset of 3 used in sys/kern/kern_time.c used for `[timers] reserved for setitimer()'.

clockid_t	Many of the timer values are implemented as int, instead of clockid_t; being pedantic they should be defined as clockid_t (int32_t).
clock_getcpuclockid	not implemented
clock_nanosleep	not implemented; requires some kernel interfaces currently missing [2].
clock_settime	kern_clock_settime does not return EINVAL for CLOCK_MONOTONIC.
itimerfix // itimespecfix	Is overloaded and unfortunately broken as it doesn't handle negative usec / nsec times.
timer_create	always returns EINVAL for CLOCK_THREAD_CPUTIME_ID due to definitions of MAX_CLOCKS; thus creating a timer for CLOCK_THREAD_CPUTIME_ID is completely impossible.

PTHREAD_KEYS_MAX	Should be defined in limits.h, not pthread.h
PTHREAD_STACK_MIN	Should be defined in limits.h, not pthread.h

mqd_t	Defined as a structure in FreeBSD. Is an integer in Linux. This means that code which assumes that mq_* APIs will return EBADF when provided a bad file descriptor (say -1) instead of segfaulting will get a nasty surprise. POSIX doesn't state what the underlying type has to be.

SIGPOLL	not implemented
struct sig_param	not implemented

daylight	broken (both in FreeBSD and in POSIX); won't fix
getdate(3)	not implemented
timezone	broken (both in FreeBSD and in POSIX); won't fix
tzname	broken (both in FreeBSD and in POSIX); won't fix