diff --git a/libc/include/machine/posix_limits.h b/libc/include/machine/posix_limits.h
index f092731..e5a299b 100644
--- a/libc/include/machine/posix_limits.h
+++ b/libc/include/machine/posix_limits.h
@@ -29,46 +29,129 @@
 #ifndef _POSIX_LIMITS_H_
 #define _POSIX_LIMITS_H_
 
-/* TODO: complete and check these. */
-#define _POSIX2_LINE_MAX            2048
-#define _POSIX2_RE_DUP_MAX          _POSIX_RE_DUP_MAX
+
+/* Any constant values here other than -1 or 200809L are explicitly specified by POSIX.1-2008. */
+/* Keep it sorted. */
+#define _POSIX_ADVISORY_INFO        -1  /* posix_madvise() not implemented */
+#define _POSIX_AIO_LISTIO_MAX       2
+#define _POSIX_AIO_MAX              1
 #define _POSIX_ARG_MAX              4096
+#define _POSIX_ASYNCHRONOUS_IO      -1  /* not implemented */
+#define _POSIX_BARRIERS             -1  /* not implemented */
 #define _POSIX_CHILD_MAX            25
 #define _POSIX_CHOWN_RESTRICTED     1  /* yes, chown requires appropriate privileges */
-#define _POSIX_FSYNC                1  /* fdatasync() supported */
-#define _POSIX_JOB_CONTROL          1  /* job control is a Linux feature */
+#define _POSIX_CLOCK_SELECTION      200809L
+#define _POSIX_CPUTIME              -1  /* clock_getcpuclockid() not implemented */
+#define _POSIX_DELAYTIMER_MAX       32
+#define _POSIX_FSYNC                200809L  /* fdatasync() supported */
 #define _POSIX_HOST_NAME_MAX        255
+#define _POSIX_IPV6                 200809L
+#define _POSIX_JOB_CONTROL          1  /* job control is a Linux feature */
 #define _POSIX_LINK_MAX             8
 #define _POSIX_LOGIN_NAME_MAX       9  /* includes trailing NUL */
-#define _POSIX_MAPPED_FILES         1  /* mmap-ed files supported */
+#define _POSIX_MAPPED_FILES         200809L  /* mmap-ed files supported */
 #define _POSIX_MAX_CANON            255
 #define _POSIX_MAX_INPUT            255
+#define _POSIX_MEMLOCK              200809L
+#define _POSIX_MEMLOCK_RANGE        200809L
+#define _POSIX_MEMORY_PROTECTION    200809L
+#define _POSIX_MESSAGE_PASSING      -1  /* not implemented */
 #define _POSIX_MONOTONIC_CLOCK      0  /* the monotonic clock may be available; ask sysconf */
+#define _POSIX_MQ_OPEN_MAX          8
+#define _POSIX_MQ_PRIO_MAX          32
 #define _POSIX_NAME_MAX             14
-#define _POSIX_NGROUPS_MAX          0
+#define _POSIX_NGROUPS_MAX          8
 #define _POSIX_NO_TRUNC             1  /* very long pathnames generate an error */
-#define _POSIX_OPEN_MAX             16
+#define _POSIX_OPEN_MAX             20
 #define _POSIX_PATH_MAX             256
 #define _POSIX_PIPE_BUF             512
-#define _POSIX_PRIORITY_SCHEDULING  1  /* priority scheduling is a Linux feature */
+#define _POSIX_PRIORITY_SCHEDULING  200809L  /* priority scheduling is a Linux feature */
+#define _POSIX_PRIORITIZED_IO       -1  /* not implemented */
+#define _POSIX_RAW_SOCKETS          200809L
+#define _POSIX_READER_WRITER_LOCKS  200809L
 #define _POSIX_REALTIME_SIGNALS     -1 /* for now, this is not supported */
+#define _POSIX_REGEXP               1
 #define _POSIX_RE_DUP_MAX           255
 #define _POSIX_SAVED_IDS            1  /* saved user ids is a Linux feature */
 #define _POSIX_SEMAPHORES           200809L
+#define _POSIX_SEM_NSEMS_MAX        256
 #define _POSIX_SEM_VALUE_MAX        32767
+#define _POSIX_SHARED_MEMORY_OBJECTS  -1  /* shm_open()/shm_unlink() not implemented */
+#define _POSIX_SHELL                1   /* system() supported */
+#define _POSIX_SIGQUEUE_MAX         32
+#define _POSIX_SPAWN                -1  /* not implemented */
+#define _POSIX_SPIN_LOCKS           -1  /* not implemented */
+#define _POSIX_SPORADIC_SERVER      -1  /* not implemented */
 #define _POSIX_SSIZE_MAX            32767
 #define _POSIX_STREAM_MAX           8
 #define _POSIX_SYMLINK_MAX          255
 #define _POSIX_SYMLOOP_MAX          8
-#define _POSIX_SYNCHRONIZED_IO      1  /* synchronized i/o supported */
-#define _POSIX_THREAD_PRIO_INHERIT  200112L  /* linux feature */
-#define _POSIX_THREAD_PRIO_PROTECT  200112L  /* linux feature */
-#define _POSIX_THREADS              1  /* we support threads */
-#define _POSIX_THREAD_STACKADDR     1  /* we support thread stack address */
-#define _POSIX_THREAD_STACKSIZE     1  /* we support thread stack size */
-#define _POSIX_TIMERS               1  /* Posix timers are supported */
+#define _POSIX_SYNCHRONIZED_IO      200809L  /* synchronized i/o supported */
+#define _POSIX_THREADS              200809L  /* we support threads */
+#define _POSIX_THREAD_ATTR_STACKADDR  200809L
+#define _POSIX_THREAD_ATTR_STACKSIZE  200809L
+#define _POSIX_THREAD_CPUTIME       200809L
+#define _POSIX_THREAD_DESTRUCTOR_ITERATIONS 4
+#define _POSIX_THREAD_KEYS_MAX      128
+#define _POSIX_THREAD_PRIORITY_SCHEDULING 200809L
+#define _POSIX_THREAD_PRIO_INHERIT  200809L  /* linux feature */
+#define _POSIX_THREAD_PRIO_PROTECT  200809L  /* linux feature */
+#define _POSIX_THREAD_PROCESS_SHARED  -1  /* not implemented */
+#define _POSIX_THREAD_ROBUST_PRIO_INHERIT -1  /* not implemented */
+#define _POSIX_THREAD_ROBUST_PRIO_PROTECT -1  /* not implemented */
+#define _POSIX_THREAD_SAFE_FUNCTIONS 200809L
+#define _POSIX_THREAD_SPORADIC_SERVER -1  /* not implemented */
+#define _POSIX_THREAD_THREADS_MAX   64
+#define _POSIX_TIMEOUTS             200809L
+#define _POSIX_TIMERS               200809L  /* Posix timers are supported */
+#define _POSIX_TIMER_MAX            32
+#define _POSIX_TRACE                -1  /* not implemented */
+#define _POSIX_TRACE_EVENT_FILTER   -1  /* not implemented */
+#define _POSIX_TRACE_INHERIT        -1  /* not implemented */
+#define _POSIX_TRACE_LOG            -1  /* not implemented */
+#define _POSIX_TRACE_NAME_MAX       8
+#define _POSIX_TRACE_SYS_MAX        8
+#define _POSIX_TRACE_USER_EVENT_MAX 32
 #define _POSIX_TTY_NAME_MAX         9  /* includes trailing NUL */
-#define _POSIX_TZNAME_MAX           3
+#define _POSIX_TYPED_MEMORY_OBJECTS -1  /* not implemented */
+#define _POSIX_TZNAME_MAX           6
 #define _POSIX_VDISABLE             '\0'
 
+#if defined(__LP64__)
+#define _POSIX_V7_ILP32_OFF32       -1
+#define _POSIX_V7_ILP32_OFFBIG      -1
+#define _POSIX_V7_LP64_OFF64         1
+#define _POSIX_V7_LPBIG_OFFBIG       1
+#else
+#define _POSIX_V7_ILP32_OFF32        1
+#define _POSIX_V7_ILP32_OFFBIG      -1
+#define _POSIX_V7_LP64_OFF64        -1
+#define _POSIX_V7_LPBIG_OFFBIG      -1
+#endif
+
+#define _POSIX2_BC_BASE_MAX         99
+#define _POSIX2_BC_DIM_MAX          2048
+#define _POSIX2_BC_SCALE_MAX        99
+#define _POSIX2_BC_STRING_MAX       1000
+#define _POSIX2_CHARCLASS_NAME_MAX  14
+#define _POSIX2_CHAR_TERM           -1  /* not implemented */
+#define _POSIX2_COLL_WEIGHTS_MAX    2
+#define _POSIX2_C_BIND              _POSIX_VERSION
+#define _POSIX2_C_DEV               -1  /* c dev utilities not implemented */
+#define _POSIX2_EXPR_NEST_MAX       32
+#define _POSIX2_LINE_MAX            2048
+#define _POSIX2_LOCALEDEF           -1  /* localedef utilitiy not implemented */
+#define _POSIX2_RE_DUP_MAX          _POSIX_RE_DUP_MAX
+#define _POSIX2_SW_DEV              -1  /* software dev utilities not implemented */
+#define _POSIX2_UPE                 -1  /* user portability utilities not implemented */
+
+#define _XOPEN_ENH_I18N             -1  /* we don't support internationalization in the C library */
+#define _XOPEN_CRYPT                -1  /* don't support X/Open Encryption */
+#define _XOPEN_IOV_MAX              16
+#define _XOPEN_LEGACY               -1  /* not support all */
+#define _XOPEN_REALTIME             -1 /* we don't support all these functions */
+#define _XOPEN_REALTIME_THREADS     -1  /* same here */
+#define _XOPEN_SHM                  -1
+#define _XOPEN_UNIX                 1
+
 #endif /* _POSIX_LIMITS_H_ */