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acassis pushed a commit to branch master
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The following commit(s) were added to refs/heads/master by this push:
new 36aefeadfe Documentation: review supported POSIX interfaces in NuttX
36aefeadfe is described below
commit 36aefeadfe665a7ba67a7baf0e7f6fb08cf05057
Author: p-szafonimateusz <p-szafonimate...@xiaomi.com>
AuthorDate: Mon May 19 13:55:38 2025 +0200
Documentation: review supported POSIX interfaces in NuttX
Add a page in the documentation listing supported and unsupported POSIX
options.
This is the first step to support POSIX Application Environment Profiles.
Signed-off-by: p-szafonimateusz <p-szafonimate...@xiaomi.com>
---
Documentation/index.rst | 1 +
Documentation/standards/index.rst | 8 +
Documentation/standards/posix.rst | 3347 +++++++++++++++++++++++++++++++++++++
3 files changed, 3356 insertions(+)
diff --git a/Documentation/index.rst b/Documentation/index.rst
index ed213834d4..1443b32636 100644
--- a/Documentation/index.rst
+++ b/Documentation/index.rst
@@ -38,6 +38,7 @@ Last Updated: |today|
faq/index.rst
debugging/index.rst
guides/index.rst
+ standards/index.rst
glossary.rst
logos/index.rst
_tags/tagsindex.rst
diff --git a/Documentation/standards/index.rst
b/Documentation/standards/index.rst
new file mode 100644
index 0000000000..878d3d4efb
--- /dev/null
+++ b/Documentation/standards/index.rst
@@ -0,0 +1,8 @@
+=========
+Standards
+=========
+
+.. toctree::
+ :maxdepth: 2
+
+ posix.rst
diff --git a/Documentation/standards/posix.rst
b/Documentation/standards/posix.rst
new file mode 100644
index 0000000000..35187b2b4d
--- /dev/null
+++ b/Documentation/standards/posix.rst
@@ -0,0 +1,3347 @@
+=====
+POSIX
+=====
+
+Apache NuttX is **not** licensed to use the POSIX trademark. NuttX uses the
+POSIX standard as a development guideline only.
+
+This page summarizes supported POSIX features in NuttX.
+
+POSIX Subprofiles
+=================
+
+POSIX PSE51 - Minimal
+---------------------
+
+Units of Functionality Requirements:
+
++------------------------------+----------------+---------+
+| Symbol | Support | Remarks |
++==============================+================+=========+
+| POSIX_ADA_LANG_SUPPORT | No | |
++------------------------------+----------------+---------+
+| `POSIX_C_LANG_JUMP`_ | Yes | |
++------------------------------+----------------+---------+
+| `POSIX_C_LANG_SUPPORT`_ | 94/105 [#fn1]_ | |
++------------------------------+----------------+---------+
+| `POSIX_DEVICE_IO`_ | Yes | |
++------------------------------+----------------+---------+
+| `POSIX_FILE_LOCKING`_ | Yes | |
++------------------------------+----------------+---------+
+| `POSIX_SINGLE_PROCESS`_ | 7/9 | |
++------------------------------+----------------+---------+
+| `POSIX_THREADS_BASE`_ | Yes | |
++------------------------------+----------------+---------+
+| `POSIX_THREADS_EXT`_ [#fn2]_ | 2/4 | |
++------------------------------+----------------+---------+
+| `XSI_THREADS_EXT`_ | 2/4 | |
++------------------------------+----------------+---------+
+
+.. [#fn1] ``fenv.h`` related functions not supported.
+.. [#fn2] In older revisions this was called ``XSI_THREAD_MUTEX_EXT``
+ and some of interfaces was moved from ``POSIX_THREADS_EXT``
+ to ``POSIX_THREADS_EXT``.
+
+POSIX.1 Option Requirements:
+
++-------------------------------------------------+-------------+----------------------------------+
+|Symbol | Support | Remarks
|
++=================================================+=============+==================================+
+|`_POSIX_CLOCK_SELECTION`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_FSYNC`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_MEMLOCK`_ | Yes [#fn3]_ |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_MEMLOCK_RANGE`_ | Yes [#fn3]_ |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_MONOTONIC_CLOCK`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_NO_TRUNC`_ | No |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_REALTIME_SIGNALS`_ | 201712L |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_SEMAPHORES`_ | 201712L |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_SHARED_MEMORY_OBJECTS`_ | 201712L |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_SYNCHRONIZED_IO`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_THREAD_ATTR_STACKADDR`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_THREAD_ATTR_STACKSIZE`_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_THREAD_CPUTIME`_ | 201712L |
|
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_THREAD_PRIO_INHERIT`_ | Yes |
``CONFIG_PRIORITY_INHERITANCE`` |
++-------------------------------------------------+-------------+----------------------------------+
+|`_POSIX_THREAD_PRIO_PROTECT`_ | Yes |
``CONFIG_PRIORITY_PROTECT`` |
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX_THREAD_PRIORITY_SCHEDULING`_ | 201712L |
|
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX_THREAD_SPORADIC_SERVER`_ | Yes |
``CONFIG_SCHED_SPORADIC`` |
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX_TIMEOUTS`_ [#fn4]_ | Yes |
|
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX_TIMERS`_ | Yes |
``!CONFIG_DISABLE_POSIX_TIMERS`` |
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX2_C_DEV`_ | Yes [#fn5]_ |
|
++-------------------------------------------------+-------------+----------------------------------+
+| `_POSIX2_SW_DEV`_ | Yes [#fn5]_ |
|
++-------------------------------------------------+-------------+----------------------------------+
+
+.. [#fn3] NuttX provides dummy implementations for ``_POSIX_MEMLOCK`` and
+ ``_POSIX_MEMLOCK_RANGE`` which is sufficient for devices without MMU,
+ but doesn't meet the requirement for devices with MMU.
+.. [#fn4] Deprecated in new revisions of POSIX. Merged into other base options.
+.. [#fn5] Requred only for the development platform.
+ For PSE54 this requirement is also for execution platform whis is
+ not supported.
+
+Requirements for Other Standards:
+
++-----------------------------+---------+---------+
+| Symbol | Support | Remarks |
++=============================+=========+=========+
+| POSIX.26 | ? | |
++-----------------------------+---------+---------+
+
+POSIX PSE52 - Real-Time Controller
+----------------------------------
+
+The Realtime Controller System Profile (PSE52) includes all features from
PSE51.
+
+Units of Functionality Requirements:
+
++-----------------------------+-------------+---------------------+
+| Symbol | Support | Remarks |
++=============================+=============+=====================+
+| `POSIX_C_LANG_MATH`_ | Yes [#fn6]_ | ``CONFIG_LIBM_XXX`` |
++-----------------------------+-------------+---------------------+
+| `POSIX_FD_MGMT`_ | Yes | |
++-----------------------------+-------------+---------------------+
+| `POSIX_FILE_SYSTEM`_ | Yes | |
++-----------------------------+-------------+---------------------+
+
+.. [#fn6] NuttX supports different libm implementations with different sets of
+ supported functions. libm support in NuttX is controlled by Kconfig
+ choice option.
+
+POSIX.1 Option Requirements
+
++------------------------------------+---------+----------------------------+
+| Symbol | Support | Remarks |
++====================================+=========+============================+
+| `_POSIX_MAPPED_FILES`_ | 201712L | |
++------------------------------------+---------+----------------------------+
+| `_POSIX_MESSAGE_PASSING`_ | Yes | ``!CONFIG_DISABLE_MQUEUE`` |
++------------------------------------+---------+----------------------------+
+| _POSIX_TRACE [#fn7]_ | No | |
++------------------------------------+---------+----------------------------+
+| _POSIX_TRACE_EVENT_FILTER [#fn7]_ | No | |
++------------------------------------+---------+----------------------------+
+| _POSIX_TRACE_LOG [#fn7]_ | No | |
++------------------------------------+---------+----------------------------+
+
+.. [#fn7] ``_POSIX_TRACE*`` are obsolete.
+
+POSIX PSE53 - Dedicated
+-----------------------
+
+The Dedicated Realtime System Profile (PSE53) includes all features from PSE52
and PSE51.
+
+Units of Functionality Requirements:
+
++-----------------------------+---------+------------------+
+| Symbol | Support | Remarks |
++=============================+=========+==================+
+| POSIX_EVENT_MGMT [#fn8]_ | Yes | |
++-----------------------------+---------+------------------+
+| `POSIX_MULTI_PROCESS`_ | 25/29 | |
++-----------------------------+---------+------------------+
+| `POSIX_NETWORKING`_ | Yes | ``CONFIG_NET`` |
++-----------------------------+---------+------------------+
+| `POSIX_PIPE`_ | Yes | ``CONFIG_PIPES`` |
++-----------------------------+---------+------------------+
+| `POSIX_SIGNAL_JUMP`_ | No | |
++-----------------------------+---------+------------------+
+
+.. [#fn8] Deprecated in new revisions of POSIX.
+ Merged into ``POSIX_DEVICE_IO``.
+
+POSIX.1 Option Requirements
+
++---------------------------------+-------------+---------------------------+
+| Symbol | Support | Remarks |
++=================================+=============+===========================+
+| `_POSIX_ASYNCHRONOUS_IO`_ | 201712L | ``CONFIG_FS_AIO`` |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_CPUTIME`_ | 201712L | |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_MEMORY_PROTECTION`_ | Yes [#fn9]_ | |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_PRIORITIZED_IO`_ | 201712L | |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_PRIORITY_SCHEDULING`_ | Yes | |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_RAW_SOCKETS`_ | Yes | |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_SPAWN`_ | 13/17 | ``CONFIG_BUILD_KERNEL`` |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_SPORADIC_SERVER`_ | Yes | ``CONFIG_SCHED_SPORADIC`` |
++---------------------------------+-------------+---------------------------+
+| `_POSIX_THREAD_PROCESS_SHARED`_ | 201712L | |
++---------------------------------+-------------+---------------------------+
+
+.. [#fn9] NuttX provides dummy implementations for ``_POSIX_MEMORY_PROTECTION``
+ which is sufficient for devices without MMU, but doesn't meet the
+ requirement for devices with MMU.
+
+POSIX PSE54 - Multipurpose
+--------------------------
+
+The Multipurpose Realtime System Profile (PSE54) includes all features from
PSE53, PSE52 and PSE51.
+
+Units of Functionality Requirements:
+
++------------------------------+---------+--------------------------------+
+| Symbol | Support | Remarks |
++==============================+=========+================================+
+| `POSIX_C_LANG_WIDE_CHAR`_ | | |
++------------------------------+---------+--------------------------------+
+| `POSIX_DEVICE_SPECIFIC`_ | 3/15 | ``CONFIG_TERMIOS=y`` |
++------------------------------+---------+--------------------------------+
+| `POSIX_FIFO`_ | Yes | ``CONFIG_DEV_FIFO_SIZE > 0`` |
++------------------------------+---------+--------------------------------+
+| `POSIX_FILE_ATTRIBUTES`_ | Yes | ``CONFIG_PSEUDOFS_ATTRIBUTES`` |
++------------------------------+---------+--------------------------------+
+| `POSIX_FILE_SYSTEM_EXT`_ | Yes | |
++------------------------------+---------+--------------------------------+
+| `POSIX_JOB_CONTROL`_ | 1/4 | |
++------------------------------+---------+--------------------------------+
+| `POSIX_REGEXP`_ | Yes | |
++------------------------------+---------+--------------------------------+
+| `POSIX_SHELL_FUNC`_ | 3/5 | |
++------------------------------+---------+--------------------------------+
+| `POSIX_STRING_MATCHING`_ | Yes | |
++------------------------------+---------+--------------------------------+
+| `POSIX_SYMBOLIC_LINKS`_ | Yes | ``CONFIG_PSEUDOFS_SOFTLINKS`` |
++------------------------------+---------+--------------------------------+
+| `POSIX_SYSTEM_DATABASE`_ | Yes | |
++------------------------------+---------+--------------------------------+
+| `POSIX_USER_GROUPS`_ | 8/10 | |
++------------------------------+---------+--------------------------------+
+| POSIX_WIDE_CHAR_IO [#fn10]_ | | |
++------------------------------+---------+--------------------------------+
+| `XSI_DYNAMIC_LINKING`_ | Yes | |
++------------------------------+---------+--------------------------------+
+| `XSI_SYSTEM_LOGGING`_ | 1/4 | |
++------------------------------+---------+--------------------------------+
+
+.. [#fn10] Deprecated in new revision of POSIX.
+ Moved to ``POSIX_WIDE_CHAR_DEVICE_IO``.
+
+POSIX.1 Option Requirements
+
++-----------------------------+---------+---------+
+| Symbol | Support | Remarks |
++=============================+=========+=========+
+| `_POSIX_ADVISORY_INFO`_ | 2/4 | |
++-----------------------------+---------+---------+
+| `_POSIX_SAVED_IDS`_ | No | |
++-----------------------------+---------+---------+
+| `_POSIX_VDISABLE`_ | No | |
++-----------------------------+---------+---------+
+| `_POSIX2_CHAR_TERM`_ | ? | |
++-----------------------------+---------+---------+
+| `_POSIX2_FORT_RUN`_ | No | |
++-----------------------------+---------+---------+
+| `_POSIX2_UPE`_ | No | |
++-----------------------------+---------+---------+
+
+Functionality Requirements
+==========================
+
+POSIX_C_LANG_JUMP
+-----------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`longjmp` | Yes |
++--------------------------------+---------+
+| :c:func:`setjmp` | Yes |
++--------------------------------+---------+
+
+POSIX_C_LANG_SUPPORT
+--------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| abs() | Yes |
++--------------------------------+---------+
+| asctime() | Yes |
++--------------------------------+---------+
+| asctime_r() | Yes |
++--------------------------------+---------+
+| atof() | Yes |
++--------------------------------+---------+
+| atoi() | Yes |
++--------------------------------+---------+
+| atol() | Yes |
++--------------------------------+---------+
+| atoll() | Yes |
++--------------------------------+---------+
+| bsearch() | Yes |
++--------------------------------+---------+
+| calloc() | Yes |
++--------------------------------+---------+
+| ctime() | Yes |
++--------------------------------+---------+
+| ctime_r() | Yes |
++--------------------------------+---------+
+| difftime() | Yes |
++--------------------------------+---------+
+| div() | Yes |
++--------------------------------+---------+
+| feclearexcept() | No |
++--------------------------------+---------+
+| fegetenv() | No |
++--------------------------------+---------+
+| fegetexceptflag() | No |
++--------------------------------+---------+
+| fegetround() | No |
++--------------------------------+---------+
+| feholdexcept() | No |
++--------------------------------+---------+
+| feraiseexcept() | No |
++--------------------------------+---------+
+| fesetenv() | No |
++--------------------------------+---------+
+| fesetexceptflag() | No |
++--------------------------------+---------+
+| fesetround() | No |
++--------------------------------+---------+
+| fetestexcept() | No |
++--------------------------------+---------+
+| feupdateenv() | No |
++--------------------------------+---------+
+| free() | Yes |
++--------------------------------+---------+
+| gmtime() | Yes |
++--------------------------------+---------+
+| gmtime_r() | Yes |
++--------------------------------+---------+
+| imaxabs() | Yes |
++--------------------------------+---------+
+| imaxdiv() | Yes |
++--------------------------------+---------+
+| isalnum() | Yes |
++--------------------------------+---------+
+| isalpha() | Yes |
++--------------------------------+---------+
+| isblank() | Yes |
++--------------------------------+---------+
+| iscntrl() | Yes |
++--------------------------------+---------+
+| isdigit() | Yes |
++--------------------------------+---------+
+| isgraph() | Yes |
++--------------------------------+---------+
+| islower() | Yes |
++--------------------------------+---------+
+| isprint() | Yes |
++--------------------------------+---------+
+| ispunct() | Yes |
++--------------------------------+---------+
+| isspace() | Yes |
++--------------------------------+---------+
+| isupper() | Yes |
++--------------------------------+---------+
+| isxdigit() | Yes |
++--------------------------------+---------+
+| labs() | Yes |
++--------------------------------+---------+
+| ldiv() | Yes |
++--------------------------------+---------+
+| llabs() | Yes |
++--------------------------------+---------+
+| lldiv() | Yes |
++--------------------------------+---------+
+| localeconv() | Yes |
++--------------------------------+---------+
+| localtime() | Yes |
++--------------------------------+---------+
+| localtime_r() | Yes |
++--------------------------------+---------+
+| malloc() | Yes |
++--------------------------------+---------+
+| memchr() | Yes |
++--------------------------------+---------+
+| memcmp() | Yes |
++--------------------------------+---------+
+| memcpy() | Yes |
++--------------------------------+---------+
+| memmove() | Yes |
++--------------------------------+---------+
+| memset() | Yes |
++--------------------------------+---------+
+| mktime() | Yes |
++--------------------------------+---------+
+| qsort() | Yes |
++--------------------------------+---------+
+| rand() | Yes |
++--------------------------------+---------+
+| rand_r() | Yes |
++--------------------------------+---------+
+| realloc() | Yes |
++--------------------------------+---------+
+| setlocale() | Yes |
++--------------------------------+---------+
+| snprintf() | Yes |
++--------------------------------+---------+
+| sprintf() | Yes |
++--------------------------------+---------+
+| srand() | Yes |
++--------------------------------+---------+
+| sscanf() | Yes |
++--------------------------------+---------+
+| strcat() | Yes |
++--------------------------------+---------+
+| strchr() | Yes |
++--------------------------------+---------+
+| strcmp() | Yes |
++--------------------------------+---------+
+| strcoll() | Yes |
++--------------------------------+---------+
+| strcpy() | Yes |
++--------------------------------+---------+
+| strcspn() | Yes |
++--------------------------------+---------+
+| strerror() | Yes |
++--------------------------------+---------+
+| strerror_r() | Yes |
++--------------------------------+---------+
+| strftime() | Yes |
++--------------------------------+---------+
+| strlen() | Yes |
++--------------------------------+---------+
+| strncat() | Yes |
++--------------------------------+---------+
+| strncmp() | Yes |
++--------------------------------+---------+
+| strncpy() | Yes |
++--------------------------------+---------+
+| strpbrk() | Yes |
++--------------------------------+---------+
+| strrchr() | Yes |
++--------------------------------+---------+
+| strspn() | Yes |
++--------------------------------+---------+
+| strstr() | Yes |
++--------------------------------+---------+
+| strtod() | Yes |
++--------------------------------+---------+
+| strtof() | Yes |
++--------------------------------+---------+
+| strtoimax() | Yes |
++--------------------------------+---------+
+| strtok() | Yes |
++--------------------------------+---------+
+| strtok_r() | Yes |
++--------------------------------+---------+
+| strtol() | Yes |
++--------------------------------+---------+
+| strtold() | Yes |
++--------------------------------+---------+
+| strtoll() | Yes |
++--------------------------------+---------+
+| strtoul() | Yes |
++--------------------------------+---------+
+| strtoull() | Yes |
++--------------------------------+---------+
+| strtoumax() | Yes |
++--------------------------------+---------+
+| strxfrm() | Yes |
++--------------------------------+---------+
+| time() | Yes |
++--------------------------------+---------+
+| tolower() | Yes |
++--------------------------------+---------+
+| toupper() | Yes |
++--------------------------------+---------+
+| tzname | Yes |
++--------------------------------+---------+
+| tzset() | Yes |
++--------------------------------+---------+
+| va_arg() | Yes |
++--------------------------------+---------+
+| va_copy() | Yes |
++--------------------------------+---------+
+| va_end() | Yes |
++--------------------------------+---------+
+| va_start() | Yes |
++--------------------------------+---------+
+| vsnprintf() | Yes |
++--------------------------------+---------+
+| vsprintf() | Yes |
++--------------------------------+---------+
+| vsscanf() | Yes |
++--------------------------------+---------+
+
+POSIX_DEVICE_IO
+---------------
+
+Device Input and Output:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`FD_CLR` | Yes |
++--------------------------------+---------+
+| :c:func:`FD_ISSET` | Yes |
++--------------------------------+---------+
+| :c:func:`FD_SET` | Yes |
++--------------------------------+---------+
+| :c:func:`FD_ZERO` | Yes |
++--------------------------------+---------+
+| :c:func:`clearerr` | Yes |
++--------------------------------+---------+
+| :c:func:`close` | Yes |
++--------------------------------+---------+
+| :c:func:`fclose` | Yes |
++--------------------------------+---------+
+| :c:func:`fdopen` | Yes |
++--------------------------------+---------+
+| :c:func:`feof` | Yes |
++--------------------------------+---------+
+| :c:func:`ferror` | Yes |
++--------------------------------+---------+
+| :c:func:`flush` | Yes |
++--------------------------------+---------+
+| :c:func:`fgetc` | Yes |
++--------------------------------+---------+
+| :c:func:`fgets` | Yes |
++--------------------------------+---------+
+| :c:func:`fileno` | Yes |
++--------------------------------+---------+
+| :c:func:`fopen` | Yes |
++--------------------------------+---------+
+| :c:func:`fprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`fputc` | Yes |
++--------------------------------+---------+
+| :c:func:`fputs` | Yes |
++--------------------------------+---------+
+| :c:func:`fread` | Yes |
++--------------------------------+---------+
+| :c:func:`freopen` | Yes |
++--------------------------------+---------+
+| :c:func:`fscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`fwrite` | Yes |
++--------------------------------+---------+
+| :c:func:`getc` | Yes |
++--------------------------------+---------+
+| :c:func:`getchar` | Yes |
++--------------------------------+---------+
+| :c:func:`open` | Yes |
++--------------------------------+---------+
+| :c:func:`perror` | Yes |
++--------------------------------+---------+
+| :c:func:`poll` | Yes |
++--------------------------------+---------+
+| posix_close() | No |
++--------------------------------+---------+
+| :c:func:`ppoll` | Yes |
++--------------------------------+---------+
+| :c:func:`printf` | Yes |
++--------------------------------+---------+
+| :c:func:`pread` | Yes |
++--------------------------------+---------+
+| :c:func:`pselect` | Yes |
++--------------------------------+---------+
+| :c:func:`putc` | Yes |
++--------------------------------+---------+
+| :c:func:`putchar` | Yes |
++--------------------------------+---------+
+| :c:func:`puts` | Yes |
++--------------------------------+---------+
+| :c:func:`pwrite` | Yes |
++--------------------------------+---------+
+| :c:func:`read` | Yes |
++--------------------------------+---------+
+| :c:func:`scanf` | Yes |
++--------------------------------+---------+
+| :c:func:`select` | Yes |
++--------------------------------+---------+
+| :c:func:`setbuf` | Yes |
++--------------------------------+---------+
+| :c:func:`setvbuf` | Yes |
++--------------------------------+---------+
+| stderr | Yes |
++--------------------------------+---------+
+| stdin | Yes |
++--------------------------------+---------+
+| stdout | Yes |
++--------------------------------+---------+
+| :c:func:`ungetc` | Yes |
++--------------------------------+---------+
+| :c:func:`vfprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`vfscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`vprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`vscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`write` | Yes |
++--------------------------------+---------+
+
+
+POSIX_FILE_LOCKING
+------------------
+
+Thread-Safe Stdio Locking:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`flockfile` | Yes |
++--------------------------------+---------+
+| :c:func:`ftrylockfile` | Yes |
++--------------------------------+---------+
+| :c:func:`funlockfile` | Yes |
++--------------------------------+---------+
+| :c:func:`getc_unlocked` | Yes |
++--------------------------------+---------+
+| :c:func:`getchar_unlocked` | Yes |
++--------------------------------+---------+
+| :c:func:`putc_unlocked` | Yes |
++--------------------------------+---------+
+| :c:func:`putchar_unlocked` | Yes |
++--------------------------------+---------+
+
+POSIX_SINGLE_PROCESS
+--------------------
+
+Single Process:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| confstr() | No |
++--------------------------------+---------+
+| environ | Yes |
++--------------------------------+---------+
+| errno | Yes |
++--------------------------------+---------+
+| :c:func:`getenv` | Yes |
++--------------------------------+---------+
+| secure_getenv() | No |
++--------------------------------+---------+
+| :c:func:`setenv` | Yes |
++--------------------------------+---------+
+| :c:func:`sysconf` | Yes |
++--------------------------------+---------+
+| :c:func:`uname` | Yes |
++--------------------------------+---------+
+| :c:func:`unsetenv` | Yes |
++--------------------------------+---------+
+
+POSIX_THREADS_BASE
+------------------
+
+Base Threads:
+
++-----------------------------------------+---------+
+| API | Support |
++=========================================+=========+
+| :c:func:`pthread_atfork` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_destroy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_getdetachstate` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_getschedparam` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_init` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_setdetachstate` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_setschedparam` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cancel` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cleanup_pop` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cleanup_push` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_broadcast` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_clockwait` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_destroy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_init` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_signal` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_timedwait` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_cond_wait` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_condattr_destroy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_condattr_init` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_create` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_detach` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_equal` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_exit` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_getspecific` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_join` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_key_create` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_key_delete` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_kill` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_clocklock` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_destroy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_init` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_lock` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_timedlock` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_trylock` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutex_unlock` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutexattr_destroy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutexattr_init` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_once` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_self` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_setcancelstate` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_setcanceltype` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_setspecific` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_sigmask` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_testcancel` | Yes |
++-----------------------------------------+---------+
+| :c:func:`sched_yield` | Yes |
++-----------------------------------------+---------+
+
+POSIX_THREADS_EXT
+-----------------
+
+Extended Threads:
+
++-------------------------------------+---------+
+| API | Support |
++=====================================+=========+
+| pthread_attr_getguardsize() | No |
++-------------------------------------+---------+
+| pthread_attr_setguardsize() | No |
++-------------------------------------+---------+
+| :c:func:`pthread_mutexattr_gettype` | Yes |
++-------------------------------------+---------+
+| :c:func:`pthread_mutexattr_settype` | Yes |
++-------------------------------------+---------+
+
+POSIX_C_LANG_MATH
+-----------------
+
+Depends on the enabled ``libm`` implementation [#fn11]_.
+
+Maths Library:
+
++--------------------------------+
+| API |
++================================+
+| CMPLX() |
++--------------------------------+
+| CMPLXF() |
++--------------------------------+
+| CMPLXL() |
++--------------------------------+
+| acos() |
++--------------------------------+
+| acosf() |
++--------------------------------+
+| acosh() |
++--------------------------------+
+| acoshf() |
++--------------------------------+
+| acoshl() |
++--------------------------------+
+| acosl() |
++--------------------------------+
+| asin() |
++--------------------------------+
+| asinf() |
++--------------------------------+
+| asinh() |
++--------------------------------+
+| asinhf() |
++--------------------------------+
+| asinhl() |
++--------------------------------+
+| asinl() |
++--------------------------------+
+| atan() |
++--------------------------------+
+| atan2() |
++--------------------------------+
+| atan2f() |
++--------------------------------+
+| atan2l() |
++--------------------------------+
+| atanf() |
++--------------------------------+
+| atanh() |
++--------------------------------+
+| atanhf() |
++--------------------------------+
+| atanhl() |
++--------------------------------+
+| atanl() |
++--------------------------------+
+| cabs() |
++--------------------------------+
+| cabsf() |
++--------------------------------+
+| cabsl() |
++--------------------------------+
+| cacos() |
++--------------------------------+
+| cacosf() |
++--------------------------------+
+| cacosh() |
++--------------------------------+
+| cacoshf() |
++--------------------------------+
+| cacoshl() |
++--------------------------------+
+| cacosl() |
++--------------------------------+
+| carg() |
++--------------------------------+
+| cargf() |
++--------------------------------+
+| cargl() |
++--------------------------------+
+| casin() |
++--------------------------------+
+| casinf() |
++--------------------------------+
+| casinh() |
++--------------------------------+
+| casinhf() |
++--------------------------------+
+| casinhl() |
++--------------------------------+
+| casinl() |
++--------------------------------+
+| catan() |
++--------------------------------+
+| catanf() |
++--------------------------------+
+| catanh() |
++--------------------------------+
+| catanhf() |
++--------------------------------+
+| catanhl() |
++--------------------------------+
+| catanl() |
++--------------------------------+
+| cbrt() |
++--------------------------------+
+| cbrtf() |
++--------------------------------+
+| cbrtl() |
++--------------------------------+
+| ccos() |
++--------------------------------+
+| ccosf() |
++--------------------------------+
+| ccosh() |
++--------------------------------+
+| ccoshf() |
++--------------------------------+
+| ccoshl() |
++--------------------------------+
+| ccosl() |
++--------------------------------+
+| ceil() |
++--------------------------------+
+| ceilf() |
++--------------------------------+
+| ceill() |
++--------------------------------+
+| cexp() |
++--------------------------------+
+| cexpf() |
++--------------------------------+
+| cexpl() |
++--------------------------------+
+| cimag() |
++--------------------------------+
+| cimagf() |
++--------------------------------+
+| cimagl() |
++--------------------------------+
+| clog() |
++--------------------------------+
+| clogf() |
++--------------------------------+
+| clogl() |
++--------------------------------+
+| conj() |
++--------------------------------+
+| conjf() |
++--------------------------------+
+| conjl() |
++--------------------------------+
+| copysign() |
++--------------------------------+
+| copysignf() |
++--------------------------------+
+| copysignl() |
++--------------------------------+
+| cos() |
++--------------------------------+
+| cosf() |
++--------------------------------+
+| cosh() |
++--------------------------------+
+| coshf() |
++--------------------------------+
+| coshl() |
++--------------------------------+
+| cosl() |
++--------------------------------+
+| cpow() |
++--------------------------------+
+| cpowf() |
++--------------------------------+
+| cpowl() |
++--------------------------------+
+| cproj() |
++--------------------------------+
+| cprojf() |
++--------------------------------+
+| cprojl() |
++--------------------------------+
+| creal() |
++--------------------------------+
+| crealf() |
++--------------------------------+
+| creall() |
++--------------------------------+
+| csin() |
++--------------------------------+
+| csinf() |
++--------------------------------+
+| csinh() |
++--------------------------------+
+| csinhf() |
++--------------------------------+
+| csinhl() |
++--------------------------------+
+| csinl() |
++--------------------------------+
+| csqrt() |
++--------------------------------+
+| csqrtf() |
++--------------------------------+
+| csqrtl() |
++--------------------------------+
+| ctan() |
++--------------------------------+
+| ctanf() |
++--------------------------------+
+| ctanh() |
++--------------------------------+
+| ctanhf() |
++--------------------------------+
+| ctanhl() |
++--------------------------------+
+| ctanl() |
++--------------------------------+
+| erf() |
++--------------------------------+
+| erfc() |
++--------------------------------+
+| erfcf() |
++--------------------------------+
+| erfcl() |
++--------------------------------+
+| erff() |
++--------------------------------+
+| erfl() |
++--------------------------------+
+| exp() |
++--------------------------------+
+| exp2() |
++--------------------------------+
+| exp2f() |
++--------------------------------+
+| exp2l() |
++--------------------------------+
+| expf() |
++--------------------------------+
+| expl() |
++--------------------------------+
+| expm1() |
++--------------------------------+
+| expm1f() |
++--------------------------------+
+| expm1l() |
++--------------------------------+
+| fabs() |
++--------------------------------+
+| fabsf() |
++--------------------------------+
+| fabsl() |
++--------------------------------+
+| fdim() |
++--------------------------------+
+| fdimf() |
++--------------------------------+
+| fdiml() |
++--------------------------------+
+| floor() |
++--------------------------------+
+| floorf() |
++--------------------------------+
+| floorl() |
++--------------------------------+
+| fma() |
++--------------------------------+
+| fmaf() |
++--------------------------------+
+| fmal() |
++--------------------------------+
+| fmax() |
++--------------------------------+
+| fmaxf() |
++--------------------------------+
+| fmaxl() |
++--------------------------------+
+| fmin() |
++--------------------------------+
+| fminf() |
++--------------------------------+
+| fminl() |
++--------------------------------+
+| fmod() |
++--------------------------------+
+| fmodf() |
++--------------------------------+
+| fmodl() |
++--------------------------------+
+| fpclassify() |
++--------------------------------+
+| frexp() |
++--------------------------------+
+| frexpf() |
++--------------------------------+
+| frexpl() |
++--------------------------------+
+| hypot() |
++--------------------------------+
+| hypotf() |
++--------------------------------+
+| hypotl() |
++--------------------------------+
+| ilogb() |
++--------------------------------+
+| ilogbf() |
++--------------------------------+
+| ilogbl() |
++--------------------------------+
+| isfinite() |
++--------------------------------+
+| isgreater() |
++--------------------------------+
+| isgreaterequal() |
++--------------------------------+
+| isinf() |
++--------------------------------+
+| isless() |
++--------------------------------+
+| islessequal() |
++--------------------------------+
+| islessgreater() |
++--------------------------------+
+| isnan() |
++--------------------------------+
+| isnormal() |
++--------------------------------+
+| isunordered() |
++--------------------------------+
+| ldexp() |
++--------------------------------+
+| ldexpf() |
++--------------------------------+
+| ldexpl() |
++--------------------------------+
+| lgamma() |
++--------------------------------+
+| lgammaf() |
++--------------------------------+
+| lgammal() |
++--------------------------------+
+| llrint() |
++--------------------------------+
+| llrintf() |
++--------------------------------+
+| llrintl() |
++--------------------------------+
+| llround() |
++--------------------------------+
+| llroundf() |
++--------------------------------+
+| llroundl() |
++--------------------------------+
+| log() |
++--------------------------------+
+| log10() |
++--------------------------------+
+| log10f() |
++--------------------------------+
+| log10l() |
++--------------------------------+
+| log1p() |
++--------------------------------+
+| log1pf() |
++--------------------------------+
+| log1pl() |
++--------------------------------+
+| log2() |
++--------------------------------+
+| log2f() |
++--------------------------------+
+| log2l() |
++--------------------------------+
+| logb() |
++--------------------------------+
+| logbf() |
++--------------------------------+
+| logbl() |
++--------------------------------+
+| logf() |
++--------------------------------+
+| logl() |
++--------------------------------+
+| lrint() |
++--------------------------------+
+| lrintf() |
++--------------------------------+
+| lrintl() |
++--------------------------------+
+| lround() |
++--------------------------------+
+| lroundf() |
++--------------------------------+
+| lroundl() |
++--------------------------------+
+| modf() |
++--------------------------------+
+| modff() |
++--------------------------------+
+| modfl() |
++--------------------------------+
+| nan() |
++--------------------------------+
+| nanf() |
++--------------------------------+
+| nanl() |
++--------------------------------+
+| nearbyint() |
++--------------------------------+
+| nearbyintf() |
++--------------------------------+
+| nearbyintl() |
++--------------------------------+
+| nextafter() |
++--------------------------------+
+| nextafterf() |
++--------------------------------+
+| nextafterl() |
++--------------------------------+
+| nexttoward() |
++--------------------------------+
+| nexttowardf() |
++--------------------------------+
+| nexttowardl() |
++--------------------------------+
+| pow() |
++--------------------------------+
+| powf() |
++--------------------------------+
+| powl() |
++--------------------------------+
+| remainder() |
++--------------------------------+
+| remainderf() |
++--------------------------------+
+| remainderl() |
++--------------------------------+
+| remquo() |
++--------------------------------+
+| remquof() |
++--------------------------------+
+| remquol() |
++--------------------------------+
+| rint() |
++--------------------------------+
+| rintf() |
++--------------------------------+
+| rintl() |
++--------------------------------+
+| round() |
++--------------------------------+
+| roundf() |
++--------------------------------+
+| roundl() |
++--------------------------------+
+| scalbln() |
++--------------------------------+
+| scalblnf() |
++--------------------------------+
+| scalblnl() |
++--------------------------------+
+| scalbn() |
++--------------------------------+
+| scalbnf() |
++--------------------------------+
+| scalbnl() |
++--------------------------------+
+| signbit() |
++--------------------------------+
+| sin() |
++--------------------------------+
+| sinf() |
++--------------------------------+
+| sinh() |
++--------------------------------+
+| sinhf() |
++--------------------------------+
+| sinhl() |
++--------------------------------+
+| sinl() |
++--------------------------------+
+| sqrt() |
++--------------------------------+
+| sqrtf() |
++--------------------------------+
+| sqrtl() |
++--------------------------------+
+| tan() |
++--------------------------------+
+| tanf() |
++--------------------------------+
+| tanh() |
++--------------------------------+
+| tanhf() |
++--------------------------------+
+| tanhl() |
++--------------------------------+
+| tanl() |
++--------------------------------+
+| tgamma() |
++--------------------------------+
+| tgammaf() |
++--------------------------------+
+| tgammal() |
++--------------------------------+
+| trunc() |
++--------------------------------+
+| truncf() |
++--------------------------------+
+| truncl() |
++--------------------------------+
+
+.. [#fn11] NuttX supports different ``libm`` implementations with different
+ sets of supported functions. ``libm`` support in NuttX is controlled
+ by Kconfig choice option.
+
+POSIX_FD_MGMT
+-------------
+
+File Descriptor Management:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`dup` | Yes |
++--------------------------------+---------+
+| :c:func:`dup2` | Yes |
++--------------------------------+---------+
+| :c:func:`dup3` | Yes |
++--------------------------------+---------+
+| :c:func:`fcntl` | Yes |
++--------------------------------+---------+
+| :c:func:`fgetpos` | Yes |
++--------------------------------+---------+
+| :c:func:`fseek` | Yes |
++--------------------------------+---------+
+| :c:func:`fseeko` | Yes |
++--------------------------------+---------+
+| :c:func:`fsetpos` | Yes |
++--------------------------------+---------+
+| :c:func:`ftell` | Yes |
++--------------------------------+---------+
+| :c:func:`ftello` | Yes |
++--------------------------------+---------+
+| :c:func:`ftruncate` | Yes |
++--------------------------------+---------+
+| :c:func:`lseek` | Yes |
++--------------------------------+---------+
+| :c:func:`rewind` | Yes |
++--------------------------------+---------+
+
+POSIX_FILE_SYSTEM
+-----------------
+
+File System:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`access` | Yes |
++--------------------------------+---------+
+| :c:func:`chdir` | Yes |
++--------------------------------+---------+
+| :c:func:`closedir` | Yes |
++--------------------------------+---------+
+| :c:func:`creat` | Yes |
++--------------------------------+---------+
+| :c:func:`fchdir` | Yes |
++--------------------------------+---------+
+| :c:func:`fpathconf` | Yes |
++--------------------------------+---------+
+| :c:func:`fstat` | Yes |
++--------------------------------+---------+
+| :c:func:`fstatvfs` | Yes |
++--------------------------------+---------+
+| :c:func:`futimens` | Yes |
++--------------------------------+---------+
+| :c:func:`getcwd` | Yes |
++--------------------------------+---------+
+| :c:func:`link` | Yes |
++--------------------------------+---------+
+| :c:func:`mkdir` | Yes |
++--------------------------------+---------+
+| :c:func:`mkostemp` | Yes |
++--------------------------------+---------+
+| :c:func:`mkstemp` | Yes |
++--------------------------------+---------+
+| :c:func:`opendir` | Yes |
++--------------------------------+---------+
+| :c:func:`pathconf` | Yes |
++--------------------------------+---------+
+| posix_getdents() | No |
++--------------------------------+---------+
+| :c:func:`readdir` | Yes |
++--------------------------------+---------+
+| :c:func:`remove` | Yes |
++--------------------------------+---------+
+| :c:func:`rename` | Yes |
++--------------------------------+---------+
+| :c:func:`rewinddir` | Yes |
++--------------------------------+---------+
+| :c:func:`rmdir` | Yes |
++--------------------------------+---------+
+| :c:func:`stat` | Yes |
++--------------------------------+---------+
+| :c:func:`statvfs` | Yes |
++--------------------------------+---------+
+| :c:func:`tmpfile` | Yes |
++--------------------------------+---------+
+| :c:func:`tmpnam` | Yes |
++--------------------------------+---------+
+| :c:func:`truncate` | Yes |
++--------------------------------+---------+
+| :c:func:`unlink` | Yes |
++--------------------------------+---------+
+
+POSIX_MULTI_PROCESS
+-------------------
+
+Multiple Processes:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`_Exit` | Yes |
++--------------------------------+---------+
+| _Fork() | No |
++--------------------------------+---------+
+| :c:func:`_exit` | Yes |
++--------------------------------+---------+
+| :c:func:`assert` | Yes |
++--------------------------------+---------+
+| :c:func:`at_quick_exit` | Yes |
++--------------------------------+---------+
+| :c:func:`atexit` | Yes |
++--------------------------------+---------+
+| :c:func:`clock` | Yes |
++--------------------------------+---------+
+| :c:func:`execl` | Yes |
++--------------------------------+---------+
+| :c:func:`execle` | Yes |
++--------------------------------+---------+
+| :c:func:`execlp` | Yes |
++--------------------------------+---------+
+| :c:func:`execv` | Yes |
++--------------------------------+---------+
+| :c:func:`execve` | Yes |
++--------------------------------+---------+
+| :c:func:`execvp` | Yes |
++--------------------------------+---------+
+| :c:func:`exit` | Yes |
++--------------------------------+---------+
+| fork() | No |
++--------------------------------+---------+
+| :c:func:`getpgrp` | Yes |
++--------------------------------+---------+
+| :c:func:`getpgid` | Yes |
++--------------------------------+---------+
+| :c:func:`getpid` | Yes |
++--------------------------------+---------+
+| :c:func:`getppid` | Yes |
++--------------------------------+---------+
+| :c:func:`getrlimit` | Yes |
++--------------------------------+---------+
+| getsid() | No |
++--------------------------------+---------+
+| :c:func:`quick_exit` | Yes |
++--------------------------------+---------+
+| :c:func:`setrlimit` | Yes |
++--------------------------------+---------+
+| setsid() | No |
++--------------------------------+---------+
+| :c:func:`sleep` | Yes |
++--------------------------------+---------+
+| :c:func:`times` | Yes |
++--------------------------------+---------+
+| :c:func:`wait` | Yes |
++--------------------------------+---------+
+| :c:func:`waitid` | Yes |
++--------------------------------+---------+
+| :c:func:`waitpid` | Yes |
++--------------------------------+---------+
+
+POSIX_NETWORKING
+----------------
+
+Networking:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`accept` | Yes |
++--------------------------------+---------+
+| :c:func:`accept4` | Yes |
++--------------------------------+---------+
+| :c:func:`be16toh` | Yes |
++--------------------------------+---------+
+| :c:func:`be32toh` | Yes |
++--------------------------------+---------+
+| :c:func:`be64toh` | Yes |
++--------------------------------+---------+
+| :c:func:`bind` | Yes |
++--------------------------------+---------+
+| :c:func:`connect` | Yes |
++--------------------------------+---------+
+| :c:func:`endhostent` | Yes |
++--------------------------------+---------+
+| :c:func:`endnetent` | Yes |
++--------------------------------+---------+
+| :c:func:`endprotoent` | Yes |
++--------------------------------+---------+
+| :c:func:`endservent` | Yes |
++--------------------------------+---------+
+| :c:func:`freeaddrinfo` | Yes |
++--------------------------------+---------+
+| :c:func:`gai_strerror` | Yes |
++--------------------------------+---------+
+| :c:func:`getaddrinfo` | Yes |
++--------------------------------+---------+
+| :c:func:`gethostent` | Yes |
++--------------------------------+---------+
+| :c:func:`gethostname` | Yes |
++--------------------------------+---------+
+| :c:func:`getnameinfo` | Yes |
++--------------------------------+---------+
+| :c:func:`getnetbyaddr` | Yes |
++--------------------------------+---------+
+| :c:func:`getnetbyname` | Yes |
++--------------------------------+---------+
+| :c:func:`getnetent` | Yes |
++--------------------------------+---------+
+| :c:func:`getpeername` | Yes |
++--------------------------------+---------+
+| :c:func:`getprotobyname` | Yes |
++--------------------------------+---------+
+| :c:func:`getprotobynumber` | Yes |
++--------------------------------+---------+
+| :c:func:`getprotoent` | Yes |
++--------------------------------+---------+
+| :c:func:`getservbyname` | Yes |
++--------------------------------+---------+
+| :c:func:`getservbyport` | Yes |
++--------------------------------+---------+
+| :c:func:`getservent` | Yes |
++--------------------------------+---------+
+| :c:func:`getsockname` | Yes |
++--------------------------------+---------+
+| :c:func:`getsockopt` | Yes |
++--------------------------------+---------+
+| :c:func:`htobe16` | Yes |
++--------------------------------+---------+
+| :c:func:`htobe32` | Yes |
++--------------------------------+---------+
+| :c:func:`htobe64` | Yes |
++--------------------------------+---------+
+| :c:func:`htole16` | Yes |
++--------------------------------+---------+
+| :c:func:`htole32` | Yes |
++--------------------------------+---------+
+| :c:func:`htole64` | Yes |
++--------------------------------+---------+
+| :c:func:`htonl` | Yes |
++--------------------------------+---------+
+| :c:func:`htons` | Yes |
++--------------------------------+---------+
+| :c:func:`if_freenameindex` | Yes |
++--------------------------------+---------+
+| :c:func:`if_indextoname` | Yes |
++--------------------------------+---------+
+| :c:func:`if_nameindex` | Yes |
++--------------------------------+---------+
+| :c:func:`if_nametoindex` | Yes |
++--------------------------------+---------+
+| :c:func:`inet_addr` | Yes |
++--------------------------------+---------+
+| :c:func:`inet_ntoa` | Yes |
++--------------------------------+---------+
+| :c:func:`inet_ntop` | Yes |
++--------------------------------+---------+
+| :c:func:`inet_pton` | Yes |
++--------------------------------+---------+
+| :c:func:`le16toh` | Yes |
++--------------------------------+---------+
+| :c:func:`le32toh` | Yes |
++--------------------------------+---------+
+| :c:func:`le64toh` | Yes |
++--------------------------------+---------+
+| :c:func:`listen` | Yes |
++--------------------------------+---------+
+| :c:func:`ntohl` | Yes |
++--------------------------------+---------+
+| :c:func:`ntohs` | Yes |
++--------------------------------+---------+
+| :c:func:`recv` | Yes |
++--------------------------------+---------+
+| :c:func:`recvfrom` | Yes |
++--------------------------------+---------+
+| :c:func:`recvmsg` | Yes |
++--------------------------------+---------+
+| :c:func:`send` | Yes |
++--------------------------------+---------+
+| :c:func:`sendmsg` | Yes |
++--------------------------------+---------+
+| :c:func:`sendto` | Yes |
++--------------------------------+---------+
+| :c:func:`sethostent` | Yes |
++--------------------------------+---------+
+| :c:func:`setnetent` | Yes |
++--------------------------------+---------+
+| :c:func:`setprotoent` | Yes |
++--------------------------------+---------+
+| :c:func:`setservent` | Yes |
++--------------------------------+---------+
+| :c:func:`setsockopt` | Yes |
++--------------------------------+---------+
+| :c:func:`shutdown` | Yes |
++--------------------------------+---------+
+| :c:func:`socket` | Yes |
++--------------------------------+---------+
+| :c:func:`sockatmark` | Yes |
++--------------------------------+---------+
+| :c:func:`socketpair` | Yes |
++--------------------------------+---------+
+
+POSIX_PIPE
+----------
+
+Pipe:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`pipe` | Yes |
++--------------------------------+---------+
+| :c:func:`pipe2` | Yes |
++--------------------------------+---------+
+
+POSIX_SIGNAL_JUMP
+-----------------
+
+Signal Jump Functions:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| siglongjmp() | No |
++--------------------------------+---------+
+| sigsetjmp() | No |
++--------------------------------+---------+
+
+POSIX_C_LANG_WIDE_CHAR
+----------------------
+
+Wide-Character ISO C Library:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| btowc() | Yes |
++--------------------------------+---------+
+| iswalnum() | Yes |
++--------------------------------+---------+
+| iswalpha() | Yes |
++--------------------------------+---------+
+| iswblank() | Yes |
++--------------------------------+---------+
+| iswcntrl() | Yes |
++--------------------------------+---------+
+| iswctype() | Yes |
++--------------------------------+---------+
+| iswdigit() | Yes |
++--------------------------------+---------+
+| iswgraph() | Yes |
++--------------------------------+---------+
+| iswlower() | Yes |
++--------------------------------+---------+
+| iswprint() | Yes |
++--------------------------------+---------+
+| iswpunct() | Yes |
++--------------------------------+---------+
+| iswspace() | Yes |
++--------------------------------+---------+
+| iswupper() | Yes |
++--------------------------------+---------+
+| iswxdigit() | Yes |
++--------------------------------+---------+
+| mblen() | Yes |
++--------------------------------+---------+
+| mbrlen() | Yes |
++--------------------------------+---------+
+| mbrtowc() | Yes |
++--------------------------------+---------+
+| mbsinit() | Yes |
++--------------------------------+---------+
+| mbsrtowcs() | Yes |
++--------------------------------+---------+
+| mbstowcs() | Yes |
++--------------------------------+---------+
+| mbtowc() | Yes |
++--------------------------------+---------+
+| swprintf() | Yes |
++--------------------------------+---------+
+| swscanf() | Yes |
++--------------------------------+---------+
+| towctrans() | Yes |
++--------------------------------+---------+
+| towlower() | Yes |
++--------------------------------+---------+
+| towupper() | Yes |
++--------------------------------+---------+
+| vswprintf() | Yes |
++--------------------------------+---------+
+| vswscanf() | Yes |
++--------------------------------+---------+
+| wcrtomb() | Yes |
++--------------------------------+---------+
+| wcscat() | Yes |
++--------------------------------+---------+
+| wcschr() | Yes |
++--------------------------------+---------+
+| wcscmp() | Yes |
++--------------------------------+---------+
+| wcscoll() | Yes |
++--------------------------------+---------+
+| wcscpy() | Yes |
++--------------------------------+---------+
+| wcscspn() | Yes |
++--------------------------------+---------+
+| wcsftime() | Yes |
++--------------------------------+---------+
+| wcslen() | Yes |
++--------------------------------+---------+
+| wcsncat() | Yes |
++--------------------------------+---------+
+| wcsncmp() | Yes |
++--------------------------------+---------+
+| wcsncpy() | Yes |
++--------------------------------+---------+
+| wcspbrk() | Yes |
++--------------------------------+---------+
+| wcsrchr() | Yes |
++--------------------------------+---------+
+| wcsrtombs() | Yes |
++--------------------------------+---------+
+| wcsspn() | Yes |
++--------------------------------+---------+
+| wcsstr() | Yes |
++--------------------------------+---------+
+| wcstod() | Yes |
++--------------------------------+---------+
+| wcstof() | Yes |
++--------------------------------+---------+
+| wcstoimax() | Yes |
++--------------------------------+---------+
+| wcstok() | Yes |
++--------------------------------+---------+
+| wcstol() | Yes |
++--------------------------------+---------+
+| wcstold() | Yes |
++--------------------------------+---------+
+| wcstoll() | Yes |
++--------------------------------+---------+
+| wcstombs() | Yes |
++--------------------------------+---------+
+| wcstoul() | Yes |
++--------------------------------+---------+
+| wcstoull() | Yes |
++--------------------------------+---------+
+| wcstoumax() | Yes |
++--------------------------------+---------+
+| wcsxfrm() | Yes |
++--------------------------------+---------+
+| wctob() | Yes |
++--------------------------------+---------+
+| wctomb() | Yes |
++--------------------------------+---------+
+| wctrans() | Yes |
++--------------------------------+---------+
+| wctype() | Yes |
++--------------------------------+---------+
+| wmemchr() | Yes |
++--------------------------------+---------+
+| wmemcmp() | Yes |
++--------------------------------+---------+
+| wmemcpy() | Yes |
++--------------------------------+---------+
+| wmemmove() | Yes |
++--------------------------------+---------+
+| wmemset() | Yes |
++--------------------------------+---------+
+
+POSIX_DEVICE_SPECIFIC
+---------------------
+
+General Terminal:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`cfgetispeed` | Yes |
++--------------------------------+---------+
+| :c:func:`cfgetospeed` | Yes |
++--------------------------------+---------+
+| :c:func:`cfsetispeed` | Yes |
++--------------------------------+---------+
+| :c:func:`cfsetospeed` | Yes |
++--------------------------------+---------+
+| ctermid() | No |
++--------------------------------+---------+
+| :c:func:`isatty` | Yes |
++--------------------------------+---------+
+| :c:func:`tcdrain` | Yes |
++--------------------------------+---------+
+| :c:func:`tcflow` | Yes |
++--------------------------------+---------+
+| :c:func:`tcflush` | Yes |
++--------------------------------+---------+
+| :c:func:`tcgetattr` | Yes |
++--------------------------------+---------+
+| tcgetwinsize() | No |
++--------------------------------+---------+
+| :c:func:`tcsendbreak` | Yes |
++--------------------------------+---------+
+| :c:func:`tcsetattr` | Yes |
++--------------------------------+---------+
+| tcsetwinsize() | No |
++--------------------------------+---------+
+| :c:func:`ttyname` | Yes |
++--------------------------------+---------+
+
+POSIX_FIFO
+----------
+
+FIFO:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`mkfifo` | Yes |
++--------------------------------+---------+
+
+POSIX_FILE_ATTRIBUTES
+---------------------
+
+File Attributes:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`chmod` | Yes |
++--------------------------------+---------+
+| :c:func:`chown` | Yes |
++--------------------------------+---------+
+| :c:func:`fchmod` | Yes |
++--------------------------------+---------+
+| :c:func:`fchown` | Yes |
++--------------------------------+---------+
+| :c:func:`umask` | Yes |
++--------------------------------+---------+
+
+POSIX_FILE_SYSTEM_EXT
+---------------------
+
+File System Extensions:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`alphasort` | Yes |
++--------------------------------+---------+
+| :c:func:`dirfd` | Yes |
++--------------------------------+---------+
+| :c:func:`getdelim` | Yes |
++--------------------------------+---------+
+| :c:func:`getline` | Yes |
++--------------------------------+---------+
+| :c:func:`mkdtemp` | Yes |
++--------------------------------+---------+
+| :c:func:`scandir` | Yes |
++--------------------------------+---------+
+
+POSIX_JOB_CONTROL
+-----------------
+
+Job Control:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| setpgid() | No |
++--------------------------------+---------+
+| tcgetpgrp() | No |
++--------------------------------+---------+
+| tcsetpgrp() | No |
++--------------------------------+---------+
+| :c:func:`tcgetsid` | Yes |
++--------------------------------+---------+
+
+POSIX_REGEXP
+------------
+
+Regular Expressions:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`regcomp` | Yes |
++--------------------------------+---------+
+| :c:func:`regerror` | Yes |
++--------------------------------+---------+
+| :c:func:`regexec` | Yes |
++--------------------------------+---------+
+| :c:func:`regfree` | Yes |
++--------------------------------+---------+
+
+POSIX_SHELL_FUNC
+----------------
+
+Shell and Utilities:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`pclose` | Yes |
++--------------------------------+---------+
+| :c:func:`popen` | Yes |
++--------------------------------+---------+
+| :c:func:`system` | Yes |
++--------------------------------+---------+
+| wordexp() | No |
++--------------------------------+---------+
+| wordfree() | No |
++--------------------------------+---------+
+
+POSIX_STRING_MATCHING
+---------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`fnmatch` | Yes |
++--------------------------------+---------+
+| :c:func:`getopt` | Yes |
++--------------------------------+---------+
+| optarg | Yes |
++--------------------------------+---------+
+| optind | Yes |
++--------------------------------+---------+
+| opterr | Yes |
++--------------------------------+---------+
+| optopt | Yes |
++--------------------------------+---------+
+
+POSIX_SYMBOLIC_LINKS
+--------------------
+
+Symbolic Links:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`lchown` | Yes |
++--------------------------------+---------+
+| :c:func:`lstat` | Yes |
++--------------------------------+---------+
+| :c:func:`readlink` | Yes |
++--------------------------------+---------+
+| :c:func:`realpath` | Yes |
++--------------------------------+---------+
+| :c:func:`symlink` | Yes |
++--------------------------------+---------+
+
+POSIX_SYSTEM_DATABASE
+---------------------
+
+System Database:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`getgrgid` | Yes |
++--------------------------------+---------+
+| :c:func:`getgrnam` | Yes |
++--------------------------------+---------+
+| :c:func:`getpwnam` | Yes |
++--------------------------------+---------+
+| :c:func:`getpwuid` | Yes |
++--------------------------------+---------+
+
+POSIX_USER_GROUPS
+-----------------
+
+User and Group:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`getegid` | Yes |
++--------------------------------+---------+
+| :c:func:`geteuid` | Yes |
++--------------------------------+---------+
+| :c:func:`getgid` | Yes |
++--------------------------------+---------+
+| getgroups() | No |
++--------------------------------+---------+
+| getlogin() | No |
++--------------------------------+---------+
+| :c:func:`getuid` | Yes |
++--------------------------------+---------+
+| :c:func:`setegid` | Yes |
++--------------------------------+---------+
+| :c:func:`seteuid` | Yes |
++--------------------------------+---------+
+| :c:func:`setgid` | Yes |
++--------------------------------+---------+
+| :c:func:`setuid` | Yes |
++--------------------------------+---------+
+
+POSIX_WIDE_CHAR_DEVICE_IO
+-------------------------
+
+Device Input and Output:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`fgetwc` | Yes |
++--------------------------------+---------+
+| :c:func:`fgetws` | Yes |
++--------------------------------+---------+
+| :c:func:`fputwc` | Yes |
++--------------------------------+---------+
+| :c:func:`fputws` | Yes |
++--------------------------------+---------+
+| :c:func:`fwide` | Yes |
++--------------------------------+---------+
+| :c:func:`fwprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`fwscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`getwc` | Yes |
++--------------------------------+---------+
+| :c:func:`getwchar` | Yes |
++--------------------------------+---------+
+| open_wmemstream() | No |
++--------------------------------+---------+
+| :c:func:`putwc` | Yes |
++--------------------------------+---------+
+| :c:func:`putwchar` | Yes |
++--------------------------------+---------+
+| :c:func:`ungetwc` | Yes |
++--------------------------------+---------+
+| :c:func:`vfwprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`vfwscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`vwprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`vwscanf` | Yes |
++--------------------------------+---------+
+| :c:func:`wprintf` | Yes |
++--------------------------------+---------+
+| :c:func:`wscanf` | Yes |
++--------------------------------+---------+
+
+XSI_C_LANG_SUPPORT
+------------------
+
+XSI General C Library:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| a64l() | No |
++--------------------------------+---------+
+| daylight | No |
++--------------------------------+---------+
+| :c:func:`drand48` | Yes |
++--------------------------------+---------+
+| :c:func:`erand48` | Yes |
++--------------------------------+---------+
+| :c:func:`ffs` | Yes |
++--------------------------------+---------+
+| :c:func:`ffsl` | Yes |
++--------------------------------+---------+
+| :c:func:`ffsll` | Yes |
++--------------------------------+---------+
+| getdate() | No |
++--------------------------------+---------+
+| :c:func:`hcreate` | Yes |
++--------------------------------+---------+
+| :c:func:`hdestroy` | Yes |
++--------------------------------+---------+
+| :c:func:`hsearch` | Yes |
++--------------------------------+---------+
+| initstate() | No |
++--------------------------------+---------+
+| insque() | No |
++--------------------------------+---------+
+| :c:func:`jrand48` | Yes |
++--------------------------------+---------+
+| l64a() | No |
++--------------------------------+---------+
+| :c:func:`lcong48` | Yes |
++--------------------------------+---------+
+| lfind() | No |
++--------------------------------+---------+
+| :c:func:`lrand48` | Yes |
++--------------------------------+---------+
+| lsearch() | No |
++--------------------------------+---------+
+| :c:func:`memccpy` | Yes |
++--------------------------------+---------+
+| :c:func:`mrand48` | Yes |
++--------------------------------+---------+
+| :c:func:`nrand48` | Yes |
++--------------------------------+---------+
+| :c:func:`random` | Yes |
++--------------------------------+---------+
+| remque() | No |
++--------------------------------+---------+
+| :c:func:`seed48` | Yes |
++--------------------------------+---------+
+| setstate() | No |
++--------------------------------+---------+
+| signgam | No |
++--------------------------------+---------+
+| :c:func:`srand48` | Yes |
++--------------------------------+---------+
+| :c:func:`srandom` | Yes |
++--------------------------------+---------+
+| :c:func:`strptime` | Yes |
++--------------------------------+---------+
+| :c:func:`swab` | Yes |
++--------------------------------+---------+
+| tdelete() | No |
++--------------------------------+---------+
+| tfind() | No |
++--------------------------------+---------+
+| timezone | No |
++--------------------------------+---------+
+| tsearch() | No |
++--------------------------------+---------+
+| twalk() | No |
++--------------------------------+---------+
+
+XSI_DBM
+-------
+
+XSI Database Management:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| dbm_clearerr() | No |
++--------------------------------+---------+
+| dbm_close() | No |
++--------------------------------+---------+
+| dbm_delete() | No |
++--------------------------------+---------+
+| dbm_error() | No |
++--------------------------------+---------+
+| dbm_fetch() | No |
++--------------------------------+---------+
+| dbm_firstkey() | No |
++--------------------------------+---------+
+| dbm_nextkey() | No |
++--------------------------------+---------+
+| dbm_open() | No |
++--------------------------------+---------+
+| dbm_store() | No |
++--------------------------------+---------+
+
+XSI_DEVICE_IO
+-------------
+
+XSI Device Input and Output:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`fmtmsg` | Yes |
++--------------------------------+---------+
+| :c:func:`readv` | Yes |
++--------------------------------+---------+
+| :c:func:`writev` | Yes |
++--------------------------------+---------+
+
+XSI_DEVICE_SPECIFIC
+-------------------
+
+XSI General Terminal:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`grantpt` | Yes |
++--------------------------------+---------+
+| :c:func:`posix_openpt` | Yes |
++--------------------------------+---------+
+| :c:func:`ptsname` | Yes |
++--------------------------------+---------+
+| :c:func:`unlockpt` | Yes |
++--------------------------------+---------+
+
+XSI_DYNAMIC_LINKING
+-------------------
+
+Dynamic Linking:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`dladdr` | Yes |
++--------------------------------+---------+
+| :c:func:`dlclose` | Yes |
++--------------------------------+---------+
+| :c:func:`dlerror` | Yes |
++--------------------------------+---------+
+| :c:func:`dlopen` | Yes |
++--------------------------------+---------+
+| :c:func:`dlsym` | Yes |
++--------------------------------+---------+
+
+XSI_FD_MGMT
+-----------
+
+XSI File Descriptor Management:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`truncate` | Yes |
++--------------------------------+---------+
+
+XSI_FILE_SYSTEM
+---------------
+
+XSI File System:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`basename` | Yes |
++--------------------------------+---------+
+| :c:func:`dirname` | Yes |
++--------------------------------+---------+
+| :c:func:`lockf` | Yes |
++--------------------------------+---------+
+| :c:func:`mknod` | Yes |
++--------------------------------+---------+
+| :c:func:`nftw` | Yes |
++--------------------------------+---------+
+| :c:func:`seekdir` | Yes |
++--------------------------------+---------+
+| :c:func:`sync` | Yes |
++--------------------------------+---------+
+| :c:func:`telldir` | Yes |
++--------------------------------+---------+
+| :c:func:`utimes` | Yes |
++--------------------------------+---------+
+
+XSI_I18N
+--------
+
+XSI Internationalization:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`catclose` | Yes |
++--------------------------------+---------+
+| :c:func:`catgets` | Yes |
++--------------------------------+---------+
+| :c:func:`catopen` | Yes |
++--------------------------------+---------+
+| :c:func:`nl_langinfo` | Yes |
++--------------------------------+---------+
+
+XSI_IPC
+-------
+
+XSI Interprocess Communication:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`ftok` | Yes |
++--------------------------------+---------+
+| :c:func:`msgctl` | Yes |
++--------------------------------+---------+
+| :c:func:`msgget` | Yes |
++--------------------------------+---------+
+| :c:func:`msgrcv` | Yes |
++--------------------------------+---------+
+| :c:func:`msgsnd` | Yes |
++--------------------------------+---------+
+| :c:func:`semctl` | No |
++--------------------------------+---------+
+| :c:func:`semget` | No |
++--------------------------------+---------+
+| :c:func:`semop` | No |
++--------------------------------+---------+
+| :c:func:`shmat` | Yes |
++--------------------------------+---------+
+| :c:func:`shmctl` | Yes |
++--------------------------------+---------+
+| :c:func:`shmdt` | Yes |
++--------------------------------+---------+
+| :c:func:`shmget` | Yes |
++--------------------------------+---------+
+
+XSI_JOB_CONTROL
+---------------
+
+XSI Job Control:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`tcgetsid` | Yes |
++--------------------------------+---------+
+
+XSI_JUMP
+--------
+
+XSI Jump Functions:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`_longjmp` | Yes |
++--------------------------------+---------+
+| :c:func:`_setjmp` | Yes |
++--------------------------------+---------+
+
+XSI_MATH
+--------
+
+Depends on the enabled ``libm`` implementation [#fn12]_.
+
+XSI Maths Library:
+
++--------------------------------+
+| API |
++================================+
+| j0() |
++--------------------------------+
+| j1() |
++--------------------------------+
+| jn() |
++--------------------------------+
+| scalb() |
++--------------------------------+
+| y0() |
++--------------------------------+
+| y1() |
++--------------------------------+
+| yn() |
++--------------------------------+
+
+.. [#fn12] NuttX supports different ``libm`` implementations with different
+ sets of supported functions. ``libm`` support in NuttX is controlled
+ by Kconfig choice option.
+
+XSI_MULTI_PROCESS
+-----------------
+
+XSI Multiple Process:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`getpgid` | Yes |
++--------------------------------+---------+
+| :c:func:`getpriority` | Yes |
++--------------------------------+---------+
+| :c:func:`getrlimit` | Yes |
++--------------------------------+---------+
+| :c:func:`getrusage` | Yes |
++--------------------------------+---------+
+| getsid() | No |
++--------------------------------+---------+
+| :c:func:`nice` | Yes |
++--------------------------------+---------+
+| setpgrp() | No |
++--------------------------------+---------+
+| :c:func:`setpriority` | Yes |
++--------------------------------+---------+
+| :c:func:`setrlimit` | Yes |
++--------------------------------+---------+
+| ulimit() | No |
++--------------------------------+---------+
+| :c:func:`usleep` | Yes |
++--------------------------------+---------+
+| :c:func:`vfork` | Yes |
++--------------------------------+---------+
+| :c:func:`waitid` | Yes |
++--------------------------------+---------+
+
+XSI_SIGNALS
+-----------
+
+XSI Signal:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| bsd_signal() | No |
++--------------------------------+---------+
+| :c:func:`killpg` | Yes |
++--------------------------------+---------+
+| :c:func:`sigaltstack` | Yes |
++--------------------------------+---------+
+| :c:func:`sighold` | Yes |
++--------------------------------+---------+
+| :c:func:`sigignore` | Yes |
++--------------------------------+---------+
+| :c:func:`siginterrupt` | Yes |
++--------------------------------+---------+
+| :c:func:`sigpause` | Yes |
++--------------------------------+---------+
+| :c:func:`sigrelse` | Yes |
++--------------------------------+---------+
+| :c:func:`sigset` | Yes |
++--------------------------------+---------+
+| ualarm() | No |
++--------------------------------+---------+
+
+XSI_SINGLE_PROCESS
+------------------
+
+XSI Single Process:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| gethostid() | No |
++--------------------------------+---------+
+| :c:func:`gettimeofday` | Yes |
++--------------------------------+---------+
+| :c:func:`putenv` | Yes |
++--------------------------------+---------+
+
+XSI_SYSTEM_DATABASE
+-------------------
+
+XSI System Database:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`endpwent` | Yes |
++--------------------------------+---------+
+| :c:func:`getpwent` | Yes |
++--------------------------------+---------+
+| :c:func:`setpwent` | Yes |
++--------------------------------+---------+
+
+XSI_SYSTEM_LOGGING
+------------------
+
+XSI System Logging:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`closelog` | No |
++--------------------------------+---------+
+| :c:func:`openlog` | No |
++--------------------------------+---------+
+| :c:func:`setlogmask` | Yes |
++--------------------------------+---------+
+| :c:func:`syslog` | Yes |
++--------------------------------+---------+
+
+XSI_THREADS_EXT
+---------------
+
+XSI Threads Extensions:
+
++---------------------------------+---------+
+| API | Support |
++=================================+=========+
+| :c:func:`pthread_attr_getstack` | Yes |
++---------------------------------+---------+
+| :c:func:`pthread_attr_setstack` | Yes |
++---------------------------------+---------+
+| pthread_getconcurrency() | No |
++---------------------------------+---------+
+| pthread_setconcurrency() | No |
++---------------------------------+---------+
+
+XSI_TIMERS
+----------
+
+XSI Timers:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`getitimer` | Yes |
++--------------------------------+---------+
+| :c:func:`setitimer` | Yes |
++--------------------------------+---------+
+
+XSI_USER_GROUPS
+---------------
+
+XSI User and Group:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| endgrent() | No |
++--------------------------------+---------+
+| endutxent() | No |
++--------------------------------+---------+
+| getgrent() | No |
++--------------------------------+---------+
+| getutxent() | No |
++--------------------------------+---------+
+| getutxid() | No |
++--------------------------------+---------+
+| getutxline() | No |
++--------------------------------+---------+
+| pututxline() | No |
++--------------------------------+---------+
+| setgrent() | No |
++--------------------------------+---------+
+| :c:func:`setregid` | Yes |
++--------------------------------+---------+
+| :c:func:`setreuid` | Yes |
++--------------------------------+---------+
+| setutxent() | No |
++--------------------------------+---------+
+
+
+XSI_WIDE_CHAR
+-------------
+
+XSI Wide-Character Library:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`wcswidth` | Yes |
++--------------------------------+---------+
+| :c:func:`wcwidth` | Yes |
++--------------------------------+---------+
+
+POSIX.1 Option Requirements
+===========================
+
+_POSIX_CLOCK_SELECTION
+----------------------
+
+Clock Selection:
+
++-------------------------------------+---------+
+| API | Support |
++=====================================+=========+
+| :c:func:`clock_nanosleep` | Yes |
++-------------------------------------+---------+
+| :c:func:`pthread_condattr_getclock` | Yes |
++-------------------------------------+---------+
+| :c:func:`pthread_condattr_setclock` | Yes |
++-------------------------------------+---------+
+
+_POSIX_FSYNC
+------------
+
+File Synchronization:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`fsync` [#fn13]_ | Yes |
++--------------------------------+---------+
+
+.. [#fn13] Revisit: why ``#undef _POSIX_FSYNC`` in ``unistd.h`` ?
+
+_POSIX_IPV6
+-----------
+
+No functions under this option.
+
+_POSIX_MEMLOCK
+--------------
+
++--------------------------------+----------------+
+| API | Support |
++================================+================+
+| :c:func:`mlockall` | Dummy [#fn14]_ |
++--------------------------------+----------------+
+| :c:func:`munlockall` | Dummy [#fn14]_ |
++--------------------------------+----------------+
+
+.. [#fn14] The function returns a success value but doesn't implement
+ the requred functionality.
+
+_POSIX_MEMLOCK_RANGE
+--------------------
+
++--------------------------------+----------------+
+| API | Support |
++================================+================+
+| :c:func:`mlock` | Dummy [#fn15]_ |
++--------------------------------+----------------+
+| :c:func:`munlock` | Dummy [#fn15]_ |
++--------------------------------+----------------+
+
+.. [#fn15] The function returns a success value but doesn't implement
+ the requred functionality.
+
+_POSIX_MONOTONIC_CLOCK
+----------------------
+
+No functions under this option.
+
+_POSIX_NO_TRUNC
+---------------
+
+No functions under this option.
+
+_POSIX_REALTIME_SIGNALS
+-----------------------
+
+Realtime Signals:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`sigqueue` | Yes |
++--------------------------------+---------+
+| :c:func:`sigtimedwait` | Yes |
++--------------------------------+---------+
+| :c:func:`sigwaitinfo` | Yes |
++--------------------------------+---------+
+
+_POSIX_SEMAPHORES
+-----------------
+
+Semaphores:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`sem_clockwait` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_close` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_destroy` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_getvalue` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_init` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_open` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_post` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_timedwait` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_trywait` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_unlink` | Yes |
++--------------------------------+---------+
+| :c:func:`sem_wait` | Yes |
++--------------------------------+---------+
+
+_POSIX_SHARED_MEMORY_OBJECTS
+----------------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`mmap` | Yes |
++--------------------------------+---------+
+| :c:func:`munmap` | Yes |
++--------------------------------+---------+
+| :c:func:`shm_open` | Yes |
++--------------------------------+---------+
+| shm_unling() | No |
++--------------------------------+---------+
+
+_POSIX_SYNCHRONIZED_IO
+----------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`fdatasync` | Yes |
++--------------------------------+---------+
+| :c:func:`fsync` | Yes |
++--------------------------------+---------+
+| :c:func:`msync` | Yes |
++--------------------------------+---------+
+
+_POSIX_THREAD_ATTR_STACKADDR
+----------------------------
+
++---------------------------------------+---------+
+| API | Support |
++=======================================+=========+
+| :c:func:`pthread_attr_getstackaddr` | Yes |
++---------------------------------------+---------+
+| :c:func:`pthread_attr_setstackaddr` | Yes |
++---------------------------------------+---------+
+
+_POSIX_THREAD_ATTR_STACKSIZE
+----------------------------
+
++---------------------------------------+---------+
+| API | Support |
++=======================================+=========+
+| :c:func:`pthread_attr_getstacksize` | Yes |
++---------------------------------------+---------+
+| :c:func:`pthread_attr_setstacksize` | Yes |
++---------------------------------------+---------+
+
+_POSIX_THREAD_CPUTIME
+---------------------
+
++-----------------------------------+---------+
+| API | Support |
++===================================+=========+
+| CLOCK_THREAD_CPUTIME_ID | Yes |
++-----------------------------------+---------+
+| :c:func:`pthread_getcpuclockid` | Yes |
++-----------------------------------+---------+
+
+_POSIX_THREAD_PRIO_INHERIT
+--------------------------
+
++-----------------------------------------+---------+
+| API | Support |
++=========================================+=========+
+| :c:func:`pthread_mutexattr_getprotocol` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_mutexattr_setprotocol` | Yes |
++-----------------------------------------+---------+
+
+_POSIX_THREAD_PRIO_PROTECT
+--------------------------
+
++-----------------------------------------------+---------+
+| API | Support |
++===============================================+=========+
+| :c:func:`pthread_mutex_getprioceiling` | Yes |
++-----------------------------------------------+---------+
+| :c:func:`pthread_mutex_setprioceiling` | Yes |
++-----------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_getprioceiling` | Yes |
++-----------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_getprotocol` | Yes |
++-----------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_setprioceiling` | Yes |
++-----------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_setprotocol` | Yes |
++-----------------------------------------------+---------+
+
+_POSIX_THREAD_PRIORITY_SCHEDULING
+---------------------------------
+
++-----------------------------------------+---------+
+| API | Support |
++=========================================+=========+
+| :c:func:`pthread_attr_getinheritsched` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_getschedpolicy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_getscope` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_setinheritsched` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_setschedpolicy` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_attr_setscope` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_getschedparam` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_setschedparam` | Yes |
++-----------------------------------------+---------+
+| :c:func:`pthread_setschedprio` | Yes |
++-----------------------------------------+---------+
+
+_POSIX_THREAD_SPORADIC_SERVER
+-----------------------------
+
+No functions under this option.
+
+_POSIX_TIMEOUTS
+---------------
+
++-------------------------------------------+---------+
+| API | Support |
++===========================================+=========+
+| :c:func:`mq_timedreceive` | Yes |
++-------------------------------------------+---------+
+| :c:func:`mq_timedsend` | Yes |
++-------------------------------------------+---------+
+| :c:func:`pthread_mutex_timedlock` | Yes |
++-------------------------------------------+---------+
+| :c:func:`pthread_rwlock_timedrdlock` | Yes |
++-------------------------------------------+---------+
+| :c:func:`pthread_rwlock_timedwrlock` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sem_timedwait` | Yes |
++-------------------------------------------+---------+
+| posix_trace_timedgetnext_event() [#fn16]_ | No |
++-------------------------------------------+---------+
+
+.. [#fn16] ``_POSIX_TRACE*`` are obsolete.
+
+_POSIX_TIMERS
+-------------
+
+Depends on ``!CONFIG_DISABLE_POSIX_TIMERS``
+
+Timers:
+
++---------------------------------+---------+
+| API | Support |
++=================================+=========+
+| :c:func:`clock_getres` | Yes |
++---------------------------------+---------+
+| :c:func:`clock_gettime` | Yes |
++---------------------------------+---------+
+| :c:func:`clock_settime` | Yes |
++---------------------------------+---------+
+| :c:func:`nanosleep` | Yes |
++---------------------------------+---------+
+| :c:func:`timer_create` | Yes |
++---------------------------------+---------+
+| :c:func:`timer_delete` | Yes |
++---------------------------------+---------+
+| :c:func:`timer_getoverrun` | Yes |
++---------------------------------+---------+
+| :c:func:`timer_gettime` | Yes |
++---------------------------------+---------+
+| :c:func:`timer_settime` | Yes |
++---------------------------------+---------+
+
+_POSIX_MAPPED_FILES
+-------------------
+
+Memory Mapped Files:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`mmap` | Yes |
++--------------------------------+---------+
+| :c:func:`munmap` | Yes |
++--------------------------------+---------+
+
+_POSIX_MESSAGE_PASSING
+----------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`mq_close` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_getattr` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_notify` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_open` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_receive` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_send` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_setattr` | Yes |
++--------------------------------+---------+
+| :c:func:`mq_unlink` | Yes |
++--------------------------------+---------+
+
+_POSIX_ASYNCHRONOUS_IO
+----------------------
+
+Depends on ``CONFIG_FS_AIO``.
+
+Asynchronous Input and Output Functions:
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`aio_cancel` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_error` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_fsync` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_read` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_return` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_suspend` | Yes |
++--------------------------------+---------+
+| :c:func:`aio_write` | Yes |
++--------------------------------+---------+
+| :c:func:`lio_listio` | Yes |
++--------------------------------+---------+
+
+_POSIX_BARRIERS
+---------------
+
++--------------------------------------------+---------+
+| API | Support |
++============================================+=========+
+| :c:func:`pthread_barrier_destroy` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrier_init` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrier_wait` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_destroy` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_init` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_getpshared` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_setpshared` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_getpshared` | Yes |
++--------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_setpshared` | Yes |
++--------------------------------------------+---------+
+
+_POSIX_CPUTIME
+--------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`clock_getcpuclockid` | Yes |
++--------------------------------+---------+
+
+_POSIX_MEMORY_PROTECTION
+------------------------
+
++--------------------------------+----------------+
+| API | Support |
++================================+================+
+| :c:func:`mprotect` | Dummy [#fn17]_ |
++--------------------------------+----------------+
+
+.. [#fn17] The function returns a success value but doesn't implement
+ the requred functionality.
+
+_POSIX_PRIORITIZED_IO
+---------------------
+
+No functions under this option.
+
+_POSIX_PRIORITY_SCHEDULING
+--------------------------
+
++-------------------------------------------+---------+
+| API | Support |
++===========================================+=========+
+| :c:func:`sched_get_priority_max` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_get_priority_min` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_getparam` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_getscheduler` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_rr_get_interval` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_setparam` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_setscheduler` | Yes |
++-------------------------------------------+---------+
+| :c:func:`sched_yield` | Yes |
++-------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getschedparam` | Yes |
++-------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setschedparam` | Yes |
++-------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getschedpolicy` | Yes |
++-------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setschedpolicy` | Yes |
++-------------------------------------------+---------+
+
+_POSIX_RAW_SOCKETS
+------------------
+
+No functions under this option.
+
+_POSIX_SPAWN
+------------
+
+Depends on ``CONFIG_BUILD_KERNEL``.
+
++---------------------------------------------+---------+
+| API | Support |
++=============================================+=========+
+| :c:func:`posix_spawn` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawn_file_actions_addclose` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawn_file_actions_adddup2` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawn_file_actions_addopen` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawn_file_actions_destroy` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawn_file_actions_init` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_destroy` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getflags` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getpgroup` | No |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getsigdefault` | No |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_getsigmask` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_init` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setflags` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setpgroup` | No |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setsigdefault` | No |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnattr_setsigmask` | Yes |
++---------------------------------------------+---------+
+| :c:func:`posix_spawnp` | Yes |
++---------------------------------------------+---------+
+
+_POSIX_SPIN_LOCKS
+-----------------
+
+Depends on ``CONFIG_PTHREAD_SPINLOCKS``.
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`pthread_spin_destroy` | Yes |
++--------------------------------+---------+
+| :c:func:`pthread_spin_init` | Yes |
++--------------------------------+---------+
+| :c:func:`pthread_spin_lock` | Yes |
++--------------------------------+---------+
+| :c:func:`pthread_spin_trylock` | Yes |
++--------------------------------+---------+
+| :c:func:`pthread_spin_unlock` | Yes |
++--------------------------------+---------+
+
+_POSIX_SPORADIC_SERVER
+----------------------
+
+No functions under this option.
+
+_POSIX_THREAD_PROCESS_SHARED
+----------------------------
+
++------------------------------------------+---------+
+| API | Support |
++==========================================+=========+
+| :c:func:`pthread_condattr_getpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_condattr_setpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_getpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_mutexattr_setpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_getpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_setpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_getpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_barrierattr_setpshared` | Yes |
++------------------------------------------+---------+
+
+_POSIX_ADVISORY_INFO
+--------------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| posix_fadvise() | No |
++--------------------------------+---------+
+| :c:func:`posix_fallocate` | Yes |
++--------------------------------+---------+
+| :c:func:`posix_memalign` | Yes |
++--------------------------------+---------+
+| posix_madvise() | Empty |
++--------------------------------+---------+
+
+_POSIX_SAVED_IDS
+----------------
+
+No functions under this option.
+
+_POSIX_VDISABLE
+---------------
+
+No functions under this option.
+
+_POSIX2_CHAR_TERM
+-----------------
+
+No utilities under this option.
+
+_POSIX2_FORT_DEV
+----------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| fort77 | No |
++--------------------------------+---------+
+
+_POSIX2_FORT_RUN
+----------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| asa | No |
++--------------------------------+---------+
+
+_POSIX2_LOCALEDEF
+-----------------
+
+No utilities under this option.
+
+_POSIX2_PBS
+-----------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| qalter | No |
++--------------------------------+---------+
+| qdel | No |
++--------------------------------+---------+
+| qhold | No |
++--------------------------------+---------+
+| qmove | No |
++--------------------------------+---------+
+| qmsg | No |
++--------------------------------+---------+
+| qrerun | No |
++--------------------------------+---------+
+| qrls | No |
++--------------------------------+---------+
+| qselect | No |
++--------------------------------+---------+
+| qsig | No |
++--------------------------------+---------+
+| qstat | No |
++--------------------------------+---------+
+| qsub | No |
++--------------------------------+---------+
+
+_POSIX2_PBS_ACCOUNTING
+----------------------
+
+No utilities under this option.
+
+_POSIX2_PBS_CHECKPOINT
+----------------------
+
+No utilities under this option.
+
+_POSIX2_PBS_LOCATE
+------------------
+
+No utilities under this option.
+
+_POSIX2_PBS_MESSAGE
+-------------------
+
+No utilities under this option.
+
+_POSIX2_PBS_TRACK
+-----------------
+
+No utilities under this option.
+
+_POSIX2_UPE
+-----------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| nm | No |
++--------------------------------+---------+
+
+_XOPEN_CRYPT
+------------
+
+Depends on ``CONFIG_CRYPTO``;
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`crypt` | Yes |
++--------------------------------+---------+
+| encrypt() | No |
++--------------------------------+---------+
+| setkey() | No |
++--------------------------------+---------+
+
+_XOPEN_ENH_I18N
+---------------
+
+No interfaces fall under this option.
+
+_XOPEN_LEGACY
+-------------
+
++--------------------------------+---------+
+| API | Support |
++================================+=========+
+| :c:func:`bcmp` | Yes |
++--------------------------------+---------+
+| :c:func:`bcopy` | Yes |
++--------------------------------+---------+
+| :c:func:`bzero` | Yes |
++--------------------------------+---------+
+| ecvt() | No |
++--------------------------------+---------+
+| fcvt() | No |
++--------------------------------+---------+
+| ftime() | No |
++--------------------------------+---------+
+| gcvt() | No |
++--------------------------------+---------+
+| getwd() | No |
++--------------------------------+---------+
+| index() | No |
++--------------------------------+---------+
+| :c:func:`mktemp` | Yes |
++--------------------------------+---------+
+| :c:func:`rindex` | Yes |
++--------------------------------+---------+
+| :c:func:`utimes` | Yes |
++--------------------------------+---------+
+| :c:func:`wcswcs` | Yes |
++--------------------------------+---------+
+
+_XOPEN_STREAMS
+--------------
+
++---------------------------------+---------+
+| API | Support |
++=================================+=========+
+| fattach() | No |
++---------------------------------+---------+
+| fdetach() | No |
++---------------------------------+---------+
+| getmsg() | No |
++---------------------------------+---------+
+| getpmsg() | No |
++---------------------------------+---------+
+| :c:func:`ioctl` | Yes |
++---------------------------------+---------+
+| isastream() | No |
++---------------------------------+---------+
+| putmsg() | No |
++---------------------------------+---------+
+| putpmsg() | No |
++---------------------------------+---------+
+
+POSIX_BARRIERS
+--------------
+
++----------------------------------------+---------+
+| API | Support |
++========================================+=========+
+| :c:func:`pthread_barrier_destroy` | Yes |
++----------------------------------------+---------+
+| :c:func:`pthread_barrier_init` | Yes |
++----------------------------------------+---------+
+| :c:func:`pthread_barrier_wait` | Yes |
++----------------------------------------+---------+
+| :c:func:`pthread_barrierattr_destroy` | Yes |
++----------------------------------------+---------+
+| :c:func:`pthread_barrierattr_init` | Yes |
++----------------------------------------+---------+
+
+POSIX_RW_LOCKS
+--------------
+
+Reader Writer Locks:
+
++------------------------------------------+---------+
+| API | Support |
++==========================================+=========+
+| :c:func:`pthread_rwlock_clockrdlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_clockwrlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_destroy` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_init` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_rdlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_timedrdlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_timedwrlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_tryrdlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_trywrlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_unlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlock_wrlock` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_destroy` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_init` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_getpshared` | Yes |
++------------------------------------------+---------+
+| :c:func:`pthread_rwlockattr_setpshared` | Yes |
++------------------------------------------+---------+
+
+_POSIX2_C_DEV
+-------------
+
++-----------------------------------+---------+
+| API | Support |
++===================================+=========+
+| c99 | No |
++-----------------------------------+---------+
+| lex | No |
++-----------------------------------+---------+
+| yacc | No |
++-----------------------------------+---------+
+
+_POSIX2_SW_DEV
+--------------
+
++-----------------------------------+---------+
+| API | Support |
++===================================+=========+
+| ar | No |
++-----------------------------------+---------+
+| make | No |
++-----------------------------------+---------+
+| strip | No |
++-----------------------------------+---------+
+| nm | No |
++-----------------------------------+---------+
+
+References
+==========
+
+* IEEE Std 1003.13, 2003 - Standardized Application Environment Profile
(AEP)—POSIX® Realtime and Embedded Application Support
+
+* `IEEE Std 1003.1, 2004 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/009604299/xrat/subprofiles.html>`_
+
+* `IEEE Std 1003.1, 2008 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/9699919799.2008edition/xrat/V4_subprofiles.html>`_
+
+* `IEEE Std 1003.1, 2013 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/9699919799.2013edition/xrat/V4_subprofiles.html>`_
+
+* `IEEE Std 1003.1, 2016 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/9699919799.2016edition/xrat/V4_subprofiles.html>`_
+
+* `IEEE Std 1003.1, 2018 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/9699919799.2018edition/xrat/V4_subprofiles.html>`_
+
+* `IEEE Std 1003.1, 2024 Subprofiling Option Groups
<https://pubs.opengroup.org/onlinepubs/9799919799/xrat/V4_subprofiles.html>`_
