S_ISBLK(), Supported
S_ISCHR(), Supported
S_ISDIR(), Supported
S_ISFIFO(), Supported
S_ISREG(), Supported
S_TYPEISMQ(), see note 3
S_TYPEISSEM(), see note 3
S_TYPEISSHM(), see note 3
WEXITSTATUS(), see note 1
WIFEXITED(), see note 1
WIFSIGNALED(), see note 1
WIFSTOPPED(), see note 1
WSTOPSIG(), see note 1
WTERMSIG(), see note 1
_exit(), Supported
abort(), Supported
abs(), Supported
access(), Supported
acos(), Supported
aio_cancel(), Supported
aio_error(), Supported
aio_fsync(), Supported
aio_read(), Supported
aio_return(), Supported
aio_suspend(), Supported
aio_write(), Supported
alarm(), Supported
asctime(), Supported
asctime_r(), Supported
asin(), Supported
assert(), Supported
atan(), Supported
atan2(), Supported
atof(), Supported
atoi(), Supported
atol(), Supported
bsearch(), Supported
calloc(), Supported
ceil(), Supported
cfgetispeed(), Supported
cfgetospeed(), Supported
cfsetispeed(), Supported
cfsetospeed(), Supported
chdir(), Supported
chmod(), Supported
chown(), Supported
clearerr(), Supported
clock_getres(), see note 2
clock_gettime(), see note 2
clock_settime(), see note 2
close(), Supported
closedir(), Supported
cos(), Supported
cosh(), Supported
creat(), Supported
ctermid(), see note 1
ctime(), Supported
ctime_r(), Supported
dup(), Supported
dup2(), Supported
execl(), see note 1
execle(), see note 1
execlp(), see note 1
execv(), see note 1
execve(), see note 1
execvp(), see note 1
exit(), Supported
exp(), Supported
fabs(), Supported
fchmod(), Supported
fclose(), Supported
fcntl(), Supported
fdatasync(), Supported
fdopen(), Supported
feof(), Supported
ferror(), Supported
fflush(), Supported
fgetc(), Supported
fgets(), Supported
fileno(), Supported
flockfile(), see note 1
floor(), Supported
fmod(), Supported
fopen(), Supported
fork(), see note 1
fpathconf(), Supported
fprintf(), Supported
fputc(), Supported
fputs(), Supported
fread(), Supported
free(), Supported
freopen(), Supported
frexp(), Supported
fscanf(), Supported
fseek(), Supported
fstat(), Supported
fsync(), Supported
ftell(), Supported
ftruncate(), Supported
ftrylockfile(), see note 1
funlockfile(), see note 1
fwrite(), Supported
getc(), Supported
getc_unlocked(), see note 1
getchar(), Supported
getchar_unlocked(), see note 1
getcwd(), Supported
getegid(), Supported
getenv(), Supported
geteuid(), Supported
getgid(), Supported
getgrgid(), Supported
getgrgid_r(), Supported
getgrnam_r(), Supported
getgrname(), Supported
getgroups(), Supported
getlogin(), Supported
getlogin_r(), Supported
getpgrp(), Supported
getpid(), Supported
getppid(), Supported
getpwnam(), Supported
getpwnam_r(), Supported
getpwuid(), Supported
getpwuid_r(), Supported
gets(), Supported
getuid(), Supported
gmtime(), Supported
gmtime_r(), Supported
isalnum(), Supported
isalpha(), Supported
isatty(), Supported
iscntrl(), Supported
isdigit(), Supported
isgraph(), Supported
islower(), Supported
isprint(), Supported
ispunct(), Supported
isspace(), Supported
isupper(), Supported
isxdigit(), Supported
kill(), Supported
ldexp(), Supported
link(), Supported
lio_listio(), Supported
localtime(), Supported
localtime_r(), Supported
log(), Supported
log10(), Supported
longjmp(), Supported
lseek(), Supported
malloc(), Supported
mkdir(), Supported
mkfifo(), see note 3
mktime(), Supported
mlock(), Not Supported
mlockall(), Not Supported
mmap(), Not Supported
modf(), Supported
mprotect(), Not Supported
mq_close(), Supported
mq_getattr(), Supported
mq_notify(), Supported
mq_open(), Supported
mq_receive(), Supported
mq_send(), Supported
mq_setattr(), Supported
mq_unlink(), Supported
msync(), Not Supported
munlock(), Not Supported
munlockall(), Not Supported
munmap(), Not Supported
nanosleep(), Supported
open(), Supported
opendir(), Supported
pathconf(), Supported
pause(), Supported
perror(), Supported
pipe(), Supported
pow(), Supported
printf(), Supported
pthread_atfork(), see note 1
pthread_attr_destroy(), Supported
pthread_attr_getdetachstate(), Supported
pthread_attr_getinheritsched(), Supported
pthread_attr_getschedparam(), Supported
pthread_attr_getschedpolicy(), Supported
pthread_attr_getscope(), Supported
pthread_attr_getstackaddr(), Supported
pthread_attr_getstacksize(), Supported
pthread_attr_init(), Supported
pthread_attr_setdetachstate(), Supported
pthread_attr_setinheritsched(), Supported
pthread_attr_setschedparam(), Supported
pthread_attr_setschedpolicy(), Supported
pthread_attr_setscope(), Supported
pthread_attr_setstackaddr(), Supported
pthread_attr_setstacksize(), Supported
pthread_cancel(), Supported
pthread_cleanup_pop(), Supported
pthread_cleanup_push(), Supported
pthread_cond_broadcast(), Supported
pthread_cond_destroy(), Supported
pthread_cond_init(), Supported
pthread_cond_signal(), Supported
pthread_cond_timedwait(), Supported
pthread_cond_wait(), Supported
pthread_condattr_destroy(), Supported
pthread_condattr_getpshared(), Supported
pthread_condattr_init(), Supported
pthread_condattr_setpshared(), Supported
pthread_create(), Supported
pthread_detach(), Supported
pthread_equal(), Supported
pthread_exit(), Supported
pthread_getschedparam(), Supported
pthread_join(), Supported
pthread_key_create(), Supported
pthread_key_delete(), Supported
pthread_key_getspecific(), Supported
pthread_key_setspecific(), Supported
pthread_kill(), Supported
pthread_mutex_destroy(), Supported
pthread_mutex_getprioceiling(), Supported
pthread_mutex_init(), Supported
pthread_mutex_lock(), Supported
pthread_mutex_setprioceiling(), Supported
pthread_mutex_trylock(), Supported
pthread_mutex_unlock(), Supported
pthread_mutexattr_destroy(), Supported
pthread_mutexattr_getprioceiling(), Supported
pthread_mutexattr_getprotocol(), Supported
pthread_mutexattr_getpshared(), Supported
pthread_mutexattr_init(), Supported
pthread_mutexattr_setprioceiling(), Supported
pthread_mutexattr_setprotocol(), Supported
pthread_mutexattr_setpshared(), Supported
pthread_once(), Supported
pthread_self(), Supported
pthread_setcancelstate(), Supported
pthread_setcanceltype(), Supported
pthread_setschedparam(), Supported
pthread_sigmask(), Supported
pthread_testcancel(), Supported
putc(), Supported
putc_unlocked(), see note 1
putchar(), Supported
putchar_unlocked(), see note 1
puts(), Supported
qsort(), Supported
rand(), Supported
rand_r(), Supported
read(), Supported
readdir(), Supported
readdir_r(), Supported
realloc(), Supported
remove(), Supported
rename(), Supported
rewind(), Supported
rewinddir(), Supported
rmdir(), Supported
scanf(), Supported
sched_get_priority_max(), Supported
sched_get_priority_min(), Supported
sched_get_priority_rr_get_interval(), Supported
sched_getparam(), Supported
sched_getscheduler(), Supported
sched_setparam(), Supported
sched_setscheduler(), Supported
sched_yield(), Supported
sem_close(), Supported
sem_destroy(), Supported
sem_getvalue(), Supported
sem_init(), Supported
sem_open(), Supported
sem_post(), Supported
sem_trywait(), Supported
sem_unlink(), Supported
sem_wait(), Supported
setbuf(), Supported
setgid(), Supported
setjmp(), Supported
setlocale(), Supported
setpgid(), Supported
setsid(), Supported
setuid(), Supported
shm_open(), Not Supported
shm_unlink(), Not Supported
sigaction(), Supported
sigaddset(), Supported
sigdelset(), Supported
sigemptyset(), Supported
sigfillset(), Supported
sigismember(), Supported
siglongjmp(), Supported
sigpending(), Supported
sigprocmask(), Supported
sigqueue(), Supported
sigsetjmp(), Supported
sigsuspend(), Supported
sigtimedwait(), Supported
sigwait(), Supported
sigwaitinfo(), Supported
sin(), Supported
sinh(), Supported
sleep(), Supported
sprintf(), Supported
sqrt(), Supported
srand(), Supported
sscanf(), Supported
stat(), Supported
strcat(), Supported
strchr(), Supported
strcmp(), Supported
strcpy(), Supported
strcspn(), Supported
strftime(), Supported
strlen(), Supported
strncat(), Supported
strncmp(), Supported
strncpy(), Supported
strpbrk(), Supported
strrchr(), Supported
strspn(), Supported
strstr(), Supported
strtok(), Supported
strtok_r(), Supported
sysconf(), Not Supported
tan(), Supported
tanh(), Supported
tcdrain(), Supported
tcflow(), Not Supported
tcflush(), Not Supported
tcgetattr(), Supported
tcgetprgrp(), see note 1
tcsendbreak(), Not Supported
tcsetattr(), Supported
tcsetprgrp(), see note 1
time(), Supported
timer_create(), Supported
timer_delete(), Supported
timer_getoverrun(), Supported
timer_gettime(), Supported
timer_settime(), Supported
times(), Supported
tmpfile(), Supported
tmpnam(), Supported
tolower(), Supported
toupper(), Supported
ttyname(), Not Supported
ttyname_r(), Not Supported
tzset(), Not Supported
umask(), Supported
uname(), Supported
ungetc(), Supported
unlink(), Supported
utime(), Supported
wait(), see note 1
waitpid(), see note 1
write(), Supported

Notes:

1.  This is not supported as it requires processes.

2.  Partial implementation.

3.  Coming soon.