diff --git a/README b/README
index 7fe7535..c91e72c 100755
--- a/README
+++ b/README
@@ -14,6 +14,7 @@ iso646.h
 libgen.h
 limits.h?
 stdbool.h
+stddef.h
 sys/un.h
 tar.h
 
@@ -24,6 +25,7 @@ The following headers are POSIX-compliant, but not XSI-compliant:
 The following headers are ISO-compliant, though not POSIX-compliant:
 
 The following headers have working code, but are still in progress:
+ctype.h (56%, missing locale-specific functions)
 math.h (3%)
 stdio.h (3% + most of printf and maybe perror?)
 stdlib.h (13%)
@@ -31,7 +33,6 @@ string.h (26%)
 time.h (4%)
 
 The following headers exist and have all definitions, but no code:
-ctype.h
 sys/utsname.h
 syslog.h
 ulimit.h
@@ -40,7 +41,6 @@ The following headers exist and are incomplete:
 float.h (45%)
 math.h (<33%)
 netinit/in.h (37%)
-stddef.h (80%)
 stdio.h (<20%)
 stdlib.h (24%)
 string.h (26%)
diff --git a/include/time.h b/include/time.h
index f7daf4d..9323d44 100644
--- a/include/time.h
+++ b/include/time.h
@@ -1,6 +1,12 @@
 #ifndef _TIME_H
 #define _TIME_H
 
+#ifdef _XOPEN_SOURCE
+#ifndef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 200908L
+#endif
+#endif
+
 #ifndef NULL
 #define NULL (void *) 0
 #endif
@@ -8,12 +14,15 @@
 #include <types/clock_t.h>
 #include <types/size_t.h>
 #include <types/time_t.h>
+#ifdef _POSIX_C_SOURCE
 #include <types/clockid_t.h>
 #include <types/timer_t.h>
-#include <types/locale_t.h>
 #include <types/pid_t.h>
+struct sigevent;
+#endif
+#include <types/locale_t.h>
 
-struct tm{
+struct tm {
   unsigned int tm_sec : 6;
   unsigned int tm_min : 6;
   unsigned int tm_hour : 5;
@@ -25,6 +34,74 @@ struct tm{
   int tm_isdst : 2;
 };
 
+struct timespec {
+  time_t tv_sec;
+  long int tv_nsec;
+};
+
+#ifdef _POSIX_C_SOURCE
+struct itimerspec {
+  struct timespec it_interval;
+  struct timespec it_value;
+};
+#endif
+
+#define CLOCKS_PER_SEC ((clock_t) 1000000)
+
+#ifdef _POSIX_C_SOURCE
+#define CLOCK_MONOTONIC 01
+#define CLOCK_PROCESS_CPUTIME_ID 02
+#define CLOCK_REALTIME 04
+#define CLOCK_THREAD_CPUTIME_ID 010
+
+#define TIMER_ABS_TIME 1
+#endif
+
+#ifdef _XOPEN_SOURCE
+extern int getdate_err;
+extern int daylight;
+extern long timezone;
+#endif
+
+clock_t clock(void);
 time_t time(time_t *);
+double difftime(time_t, time_t);
+time_t mktime(struct tm *);
+int timespec_get(struct timespec *, int);
+char * asctime(const struct tm *);
+char * ctime(const time_t *);
+struct tm * gmtime(const time_t *);
+struct tm * localtime(const time_t *);
+size_t strftime(char * restrict, size_t, const char * restrict, 
+                const struct tm * restrict);
+
+
+#ifdef _POSIX_C_SOURCE
+char * asctime_r(const struct tm * restrict, char * restrict);
+int clock_getcpuclockid(pid_t, clockid_t *);
+int clock_getres(clockid_t, struct timespec *);
+int clock_gettime(clockid_t, struct timespec *);
+int clock_nanosleep(clockid_t, int, const struct timespec *, struct timespec *);
+int clock_settime(clockid_t, const struct timespec *);
+char * ctime_r(const time_t *, char *);
+struct tm * gmtime_r(const time_t * restrict, struct tm * restrict);
+struct tm * localtime_r(const time_t * restrict, struct tm * restrict);
+int nanosleep(const struct timespec *, struct timespec *);
+size_t strftime_l(char * restrict, size_t, const char * restrict,
+                  const struct tm * restrict, locale_t);
+int timer_create(clockid_t, struct sigevent * restrict, timer_t * restrict);
+int timer_delete(timer_t);
+int timer_getoverrun(timer_t);
+int timer_gettime(timer_t, struct itimerspec *);
+int timer_settime(timer_t, int, const struct itimerspec * restrict, 
+                  struct itimerspec * restrict);
+void tzset(void);
+#endif
+
+#ifdef _XOPEN_SOURCE
+struct time * getdate(const char *);
+char * strptime(const char * restrict, const char * restrict, 
+                struct tm * restrict);
+#endif
 
 #endif /* not _HEADER */