System interfaces compatible with GNU or Linux extensions:
__mempcpy
accept4
argz_add
argz_add_sep
argz_append
argz_count
argz_create
argz_create_sep
argz_delete
argz_extract
argz_insert
argz_next
argz_replace
argz_stringify
asnprintf
asprintf
asprintf_r
basename (see the section called “Implementation Notes”)
canonicalize_file_name
clearenv
clog10
clog10f
clog10l
close_range (see the section called “Implementation Notes”)
crypt_r (available in external "crypt" library)
dladdr (see the section called “Implementation Notes”)
dremf
dup3
envz_add
envz_entry
envz_get
envz_merge
envz_remove
envz_strip
error
error_at_line
euidaccess
execvpe
exp10
exp10f
exp10l
fallocate (see the section called “Implementation Notes”)
fcloseall
fcloseall_r
fedisableexcept
feenableexcept
fegetexcept
ffsl
ffsll
fgets_unlocked
fgetwc_unlocked
fgetws_unlocked
fgetxattr
flistxattr
fopencookie
fputs_unlocked
fputwc_unlocked
fputws_unlocked
fremovexattr
fsetxattr
get_avphys_pages
get_current_dir_name
get_nprocs
get_nprocs_conf
get_phys_pages
getmntent_r
getopt_long
getopt_long_only
getpt
getwc_unlocked
getwchar_unlocked
getxattr
lgetxattr
listxattr
llistxattr
lremovexattr
lsetxattr
memmem
mempcpy
memrchr
mkostemp
mkostemps
pipe2
posix_spawn_file_actions_addchdir_np
posix_spawn_file_actions_addfchdir_np
pow10
pow10f
pow10l
ppoll
pthread_cond_clockwait
pthread_getaffinity_np
pthread_getattr_np
pthread_getname_np
pthread_mutex_clocklock
pthread_rwlock_clockrdlock
pthread_rwlock_clockwrlock
pthread_setaffinity_np
pthread_setname_np
pthread_sigqueue
pthread_timedjoin_np
pthread_tryjoin_np
ptsname_r
putwc_unlocked
putwchar_unlocked
renameat2 (see the section called “Implementation Notes”)
qsort_r (see the section called “Implementation Notes”)
quotactl
rawmemchr
removexattr
scandirat
sched_getaffinity
sched_getcpu
sched_setaffinity
secure_getenv
sem_clockwait
setxattr
signalfd
sincos
sincosf
sincosl
strchrnul
strptime_l
strtod_l
strtof_l
strtol_l
strtold_l
strtoll_l
strtoul_l
strtoull_l
strverscmp
sysinfo
tdestroy
timerfd_create
timerfd_gettime
timerfd_settime
timegm
timelocal
toascii_l
updwtmpx
utmpxname
vasnprintf
vasprintf
vasprintf_r
versionsort
wcsftime_l
wcstod_l
wcstof_l
wcstol_l
wcstold_l
wcstoll_l
wcstoul_l
wcstoull_l
wmempcpy