Index: uspace/lib/c/Makefile
===================================================================
--- uspace/lib/c/Makefile	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/Makefile	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -71,4 +71,5 @@
 	generic/device/hw_res_parsed.c \
 	generic/device/char_dev.c \
+	generic/device/clock_dev.c \
 	generic/device/graph_dev.c \
 	generic/device/nic.c \
Index: uspace/lib/c/generic/async.c
===================================================================
--- uspace/lib/c/generic/async.c	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/generic/async.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -638,5 +638,5 @@
 	
 	if (usecs) {
-		gettimeofday(&conn->wdata.to_event.expires, NULL);
+		getuptime(&conn->wdata.to_event.expires);
 		tv_add(&conn->wdata.to_event.expires, usecs);
 	} else
@@ -967,5 +967,5 @@
 {
 	struct timeval tv;
-	gettimeofday(&tv, NULL);
+	getuptime(&tv);
 	
 	futex_down(&async_futex);
@@ -1024,5 +1024,5 @@
 			
 			struct timeval tv;
-			gettimeofday(&tv, NULL);
+			getuptime(&tv);
 			
 			if (tv_gteq(&tv, &waiter->to_event.expires)) {
@@ -1331,5 +1331,5 @@
 		timeout = 0;
 
-	gettimeofday(&msg->wdata.to_event.expires, NULL);
+	getuptime(&msg->wdata.to_event.expires);
 	tv_add(&msg->wdata.to_event.expires, timeout);
 	
@@ -1413,5 +1413,5 @@
 	msg->wdata.fid = fibril_get_id();
 	
-	gettimeofday(&msg->wdata.to_event.expires, NULL);
+	getuptime(&msg->wdata.to_event.expires);
 	tv_add(&msg->wdata.to_event.expires, timeout);
 	
Index: uspace/lib/c/generic/device/clock_dev.c
===================================================================
--- uspace/lib/c/generic/device/clock_dev.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/c/generic/device/clock_dev.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+ /** @addtogroup libc
+ * @{
+ */
+/** @file
+ */
+
+#include <ipc/dev_iface.h>
+#include <device/clock_dev.h>
+#include <errno.h>
+#include <async.h>
+#include <time.h>
+
+/** Read the current time from the device
+ *
+ * @param sess     Session of the device
+ * @param t        The current time that will be read from the device
+ *
+ * @return         EOK on success or a negative error code
+ */
+int
+clock_dev_time_get(async_sess_t *sess, struct tm *t)
+{
+	aid_t req;
+	int ret;
+
+	async_exch_t *exch = async_exchange_begin(sess);
+
+	req = async_send_1(exch, DEV_IFACE_ID(CLOCK_DEV_IFACE),
+	    CLOCK_DEV_TIME_GET, NULL);
+	ret = async_data_read_start(exch, t, sizeof(*t));
+
+	async_exchange_end(exch);
+
+	sysarg_t rc;
+	if (ret != EOK) {
+		async_wait_for(req, &rc);
+		if (rc == EOK)
+			return ret;
+	}
+
+	async_wait_for(req, &rc);
+	return (int)rc;
+}
+
+/** Set the current time
+ *
+ * @param sess   Session of the device
+ * @param t      The current time that will be written to the device
+ *
+ * @return       EOK on success or a negative error code
+ */
+int
+clock_dev_time_set(async_sess_t *sess, struct tm *t)
+{
+	aid_t req;
+	int ret;
+
+	async_exch_t *exch = async_exchange_begin(sess);
+
+	req = async_send_1(exch, DEV_IFACE_ID(CLOCK_DEV_IFACE),
+	    CLOCK_DEV_TIME_SET, NULL);
+	ret = async_data_write_start(exch, t, sizeof(*t));
+
+	async_exchange_end(exch);
+
+	sysarg_t rc;
+	if (ret != EOK) {
+		async_wait_for(req, &rc);
+		if (rc == EOK)
+			return ret;
+	}
+
+	async_wait_for(req, &rc);
+	return (int)rc;
+}
+
+/** @}
+ */
+
Index: uspace/lib/c/generic/fibril_synch.c
===================================================================
--- uspace/lib/c/generic/fibril_synch.c	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/generic/fibril_synch.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -379,5 +379,5 @@
 	futex_down(&async_futex);
 	if (timeout) {
-		gettimeofday(&wdata.to_event.expires, NULL);
+		getuptime(&wdata.to_event.expires);
 		tv_add(&wdata.to_event.expires, timeout);
 		async_insert_timeout(&wdata);
Index: uspace/lib/c/generic/time.c
===================================================================
--- uspace/lib/c/generic/time.c	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/generic/time.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -1,4 +1,6 @@
 /*
  * Copyright (c) 2006 Ondrej Palkovsky
+ * Copyright (c) 2011 Petr Koupy
+ * Copyright (c) 2011 Jiri Zarevucky
  * All rights reserved.
  *
@@ -43,5 +45,14 @@
 #include <ddi.h>
 #include <libc.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <assert.h>
 #include <unistd.h>
+#include <loc.h>
+#include <device/clock_dev.h>
+#include <malloc.h>
+
+#define ASCTIME_BUF_LEN 26
 
 /** Pointer to kernel shared variables with time */
@@ -52,4 +63,337 @@
 } *ktime = NULL;
 
+/* Helper functions ***********************************************************/
+
+#define HOURS_PER_DAY (24)
+#define MINS_PER_HOUR (60)
+#define SECS_PER_MIN (60)
+#define MINS_PER_DAY (MINS_PER_HOUR * HOURS_PER_DAY)
+#define SECS_PER_HOUR (SECS_PER_MIN * MINS_PER_HOUR)
+#define SECS_PER_DAY (SECS_PER_HOUR * HOURS_PER_DAY)
+
+/**
+ * Checks whether the year is a leap year.
+ *
+ * @param year Year since 1900 (e.g. for 1970, the value is 70).
+ * @return true if year is a leap year, false otherwise
+ */
+static bool _is_leap_year(time_t year)
+{
+	year += 1900;
+
+	if (year % 400 == 0)
+		return true;
+	if (year % 100 == 0)
+		return false;
+	if (year % 4 == 0)
+		return true;
+	return false;
+}
+
+/**
+ * Returns how many days there are in the given month of the given year.
+ * Note that year is only taken into account if month is February.
+ *
+ * @param year Year since 1900 (can be negative).
+ * @param mon Month of the year. 0 for January, 11 for December.
+ * @return Number of days in the specified month.
+ */
+static int _days_in_month(time_t year, time_t mon)
+{
+	assert(mon >= 0 && mon <= 11);
+
+	static int month_days[] =
+		{ 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+
+	if (mon == 1) {
+		year += 1900;
+		/* february */
+		return _is_leap_year(year) ? 29 : 28;
+	} else {
+		return month_days[mon];
+	}
+}
+
+/**
+ * For specified year, month and day of month, returns which day of that year
+ * it is.
+ *
+ * For example, given date 2011-01-03, the corresponding expression is:
+ *     _day_of_year(111, 0, 3) == 2
+ *
+ * @param year Year (year 1900 = 0, can be negative).
+ * @param mon Month (January = 0).
+ * @param mday Day of month (First day is 1).
+ * @return Day of year (First day is 0).
+ */
+static int _day_of_year(time_t year, time_t mon, time_t mday)
+{
+	static int mdays[] =
+	    { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
+	static int leap_mdays[] =
+	    { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335 };
+
+	return (_is_leap_year(year) ? leap_mdays[mon] : mdays[mon]) + mday - 1;
+}
+
+/**
+ * Integer division that rounds to negative infinity.
+ * Used by some functions in this file.
+ *
+ * @param op1 Dividend.
+ * @param op2 Divisor.
+ * @return Rounded quotient.
+ */
+static time_t _floor_div(time_t op1, time_t op2)
+{
+	if (op1 >= 0 || op1 % op2 == 0) {
+		return op1 / op2;
+	} else {
+		return op1 / op2 - 1;
+	}
+}
+
+/**
+ * Modulo that rounds to negative infinity.
+ * Used by some functions in this file.
+ *
+ * @param op1 Dividend.
+ * @param op2 Divisor.
+ * @return Remainder.
+ */
+static time_t _floor_mod(time_t op1, time_t op2)
+{
+	int div = _floor_div(op1, op2);
+
+	/* (a / b) * b + a % b == a */
+	/* thus, a % b == a - (a / b) * b */
+
+	int result = op1 - div * op2;
+	
+	/* Some paranoid checking to ensure I didn't make a mistake here. */
+	assert(result >= 0);
+	assert(result < op2);
+	assert(div * op2 + result == op1);
+	
+	return result;
+}
+
+/**
+ * Number of days since the Epoch.
+ * Epoch is 1970-01-01, which is also equal to day 0.
+ *
+ * @param year Year (year 1900 = 0, may be negative).
+ * @param mon Month (January = 0).
+ * @param mday Day of month (first day = 1).
+ * @return Number of days since the Epoch.
+ */
+static time_t _days_since_epoch(time_t year, time_t mon, time_t mday)
+{
+	return (year - 70) * 365 + _floor_div(year - 69, 4) -
+	    _floor_div(year - 1, 100) + _floor_div(year + 299, 400) +
+	    _day_of_year(year, mon, mday);
+}
+
+/**
+ * Seconds since the Epoch. see also _days_since_epoch().
+ * 
+ * @param tm Normalized broken-down time.
+ * @return Number of seconds since the epoch, not counting leap seconds.
+ */
+static time_t _secs_since_epoch(const struct tm *tm)
+{
+	return _days_since_epoch(tm->tm_year, tm->tm_mon, tm->tm_mday) *
+	    SECS_PER_DAY + tm->tm_hour * SECS_PER_HOUR +
+	    tm->tm_min * SECS_PER_MIN + tm->tm_sec;
+}
+
+/**
+ * Which day of week the specified date is.
+ * 
+ * @param year Year (year 1900 = 0).
+ * @param mon Month (January = 0).
+ * @param mday Day of month (first = 1).
+ * @return Day of week (Sunday = 0).
+ */
+static int _day_of_week(time_t year, time_t mon, time_t mday)
+{
+	/* 1970-01-01 is Thursday */
+	return _floor_mod((_days_since_epoch(year, mon, mday) + 4), 7);
+}
+
+/**
+ * Normalizes the broken-down time and optionally adds specified amount of
+ * seconds.
+ * 
+ * @param tm Broken-down time to normalize.
+ * @param sec_add Seconds to add.
+ * @return 0 on success, -1 on overflow
+ */
+static int _normalize_time(struct tm *tm, time_t sec_add)
+{
+	// TODO: DST correction
+
+	/* Set initial values. */
+	time_t sec = tm->tm_sec + sec_add;
+	time_t min = tm->tm_min;
+	time_t hour = tm->tm_hour;
+	time_t day = tm->tm_mday - 1;
+	time_t mon = tm->tm_mon;
+	time_t year = tm->tm_year;
+
+	/* Adjust time. */
+	min += _floor_div(sec, SECS_PER_MIN);
+	sec = _floor_mod(sec, SECS_PER_MIN);
+	hour += _floor_div(min, MINS_PER_HOUR);
+	min = _floor_mod(min, MINS_PER_HOUR);
+	day += _floor_div(hour, HOURS_PER_DAY);
+	hour = _floor_mod(hour, HOURS_PER_DAY);
+
+	/* Adjust month. */
+	year += _floor_div(mon, 12);
+	mon = _floor_mod(mon, 12);
+
+	/* Now the difficult part - days of month. */
+	
+	/* First, deal with whole cycles of 400 years = 146097 days. */
+	year += _floor_div(day, 146097) * 400;
+	day = _floor_mod(day, 146097);
+	
+	/* Then, go in one year steps. */
+	if (mon <= 1) {
+		/* January and February. */
+		while (day > 365) {
+			day -= _is_leap_year(year) ? 366 : 365;
+			year++;
+		}
+	} else {
+		/* Rest of the year. */
+		while (day > 365) {
+			day -= _is_leap_year(year + 1) ? 366 : 365;
+			year++;
+		}
+	}
+	
+	/* Finally, finish it off month per month. */
+	while (day >= _days_in_month(year, mon)) {
+		day -= _days_in_month(year, mon);
+		mon++;
+		if (mon >= 12) {
+			mon -= 12;
+			year++;
+		}
+	}
+	
+	/* Calculate the remaining two fields. */
+	tm->tm_yday = _day_of_year(year, mon, day + 1);
+	tm->tm_wday = _day_of_week(year, mon, day + 1);
+	
+	/* And put the values back to the struct. */
+	tm->tm_sec = (int) sec;
+	tm->tm_min = (int) min;
+	tm->tm_hour = (int) hour;
+	tm->tm_mday = (int) day + 1;
+	tm->tm_mon = (int) mon;
+	
+	/* Casts to work around libc brain-damage. */
+	if (year > ((int)INT_MAX) || year < ((int)INT_MIN)) {
+		tm->tm_year = (year < 0) ? ((int)INT_MIN) : ((int)INT_MAX);
+		return -1;
+	}
+	
+	tm->tm_year = (int) year;
+	return 0;
+}
+
+/**
+ * Which day the week-based year starts on, relative to the first calendar day.
+ * E.g. if the year starts on December 31st, the return value is -1.
+ *
+ * @param Year since 1900.
+ * @return Offset of week-based year relative to calendar year.
+ */
+static int _wbyear_offset(int year)
+{
+	int start_wday = _day_of_week(year, 0, 1);
+	return _floor_mod(4 - start_wday, 7) - 3;
+}
+
+/**
+ * Returns week-based year of the specified time.
+ *
+ * @param tm Normalized broken-down time.
+ * @return Week-based year.
+ */
+static int _wbyear(const struct tm *tm)
+{
+	int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
+	if (day < 0) {
+		/* Last week of previous year. */
+		return tm->tm_year - 1;
+	}
+	if (day > 364 + _is_leap_year(tm->tm_year)) {
+		/* First week of next year. */
+		return tm->tm_year + 1;
+	}
+	/* All the other days are in the calendar year. */
+	return tm->tm_year;
+}
+
+/**
+ * Week number of the year, assuming weeks start on sunday.
+ * The first Sunday of January is the first day of week 1;
+ * days in the new year before this are in week 0.
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (0 - 53).
+ */
+static int _sun_week_number(const struct tm *tm)
+{
+	int first_day = (7 - _day_of_week(tm->tm_year, 0, 1)) % 7;
+	return (tm->tm_yday - first_day + 7) / 7;
+}
+
+/**
+ * Week number of the year, assuming weeks start on monday.
+ * If the week containing January 1st has four or more days in the new year,
+ * then it is considered week 1. Otherwise, it is the last week of the previous
+ * year, and the next week is week 1. Both January 4th and the first Thursday
+ * of January are always in week 1.
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (1 - 53).
+ */
+static int _iso_week_number(const struct tm *tm)
+{
+	int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
+	if (day < 0) {
+		/* Last week of previous year. */
+		return 53;
+	}
+	if (day > 364 + _is_leap_year(tm->tm_year)) {
+		/* First week of next year. */
+		return 1;
+	}
+	/* All the other days give correct answer. */
+	return (day / 7 + 1);
+}
+
+/**
+ * Week number of the year, assuming weeks start on monday.
+ * The first Monday of January is the first day of week 1;
+ * days in the new year before this are in week 0. 
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (0 - 53).
+ */
+static int _mon_week_number(const struct tm *tm)
+{
+	int first_day = (1 - _day_of_week(tm->tm_year, 0, 1)) % 7;
+	return (tm->tm_yday - first_day + 7) / 7;
+}
+
+/******************************************************************************/
+
+
 /** Add microseconds to given timeval.
  *
@@ -139,4 +483,67 @@
  */
 int gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	int rc;
+	struct tm t;
+	category_id_t cat_id;
+	size_t svc_cnt;
+	service_id_t *svc_ids = NULL;
+	service_id_t svc_id;
+	char *svc_name = NULL;
+
+	static async_sess_t *clock_conn = NULL;
+
+	if (tz) {
+		tz->tz_minuteswest = 0;
+		tz->tz_dsttime = DST_NONE;
+	}
+
+	if (clock_conn == NULL) {
+		rc = loc_category_get_id("clock", &cat_id, IPC_FLAG_BLOCKING);
+		if (rc != EOK)
+			goto ret_uptime;
+
+		rc = loc_category_get_svcs(cat_id, &svc_ids, &svc_cnt);
+		if (rc != EOK)
+			goto ret_uptime;
+
+		if (svc_cnt == 0)
+			goto ret_uptime;
+
+		rc = loc_service_get_name(svc_ids[0], &svc_name);
+		if (rc != EOK)
+			goto ret_uptime;
+
+		rc = loc_service_get_id(svc_name, &svc_id, 0);
+		if (rc != EOK)
+			goto ret_uptime;
+
+		clock_conn = loc_service_connect(EXCHANGE_SERIALIZE,
+		    svc_id, IPC_FLAG_BLOCKING);
+		if (!clock_conn)
+			goto ret_uptime;
+	}
+
+	rc = clock_dev_time_get(clock_conn, &t);
+	if (rc != EOK)
+		goto ret_uptime;
+
+	tv->tv_usec = 0;
+	tv->tv_sec = mktime(&t);
+
+	free(svc_name);
+	free(svc_ids);
+
+	return EOK;
+
+ret_uptime:
+
+	free(svc_name);
+	free(svc_ids);
+
+	return getuptime(tv);
+}
+
+int getuptime(struct timeval *tv)
 {
 	if (ktime == NULL) {
@@ -160,9 +567,4 @@
 	}
 	
-	if (tz) {
-		tz->tz_minuteswest = 0;
-		tz->tz_dsttime = DST_NONE;
-	}
-	
 	sysarg_t s2 = ktime->seconds2;
 	
@@ -178,5 +580,5 @@
 	} else
 		tv->tv_sec = s1;
-	
+
 	return 0;
 }
@@ -229,4 +631,355 @@
 }
 
+/**
+ * This function first normalizes the provided broken-down time
+ * (moves all values to their proper bounds) and then tries to
+ * calculate the appropriate time_t representation.
+ *
+ * @param tm Broken-down time.
+ * @return time_t representation of the time, undefined value on overflow.
+ */
+time_t mktime(struct tm *tm)
+{
+	// TODO: take DST flag into account
+	// TODO: detect overflow
+
+	_normalize_time(tm, 0);
+	return _secs_since_epoch(tm);
+}
+
+/**
+ * Convert time and date to a string, based on a specified format and
+ * current locale.
+ * 
+ * @param s Buffer to write string to.
+ * @param maxsize Size of the buffer.
+ * @param format Format of the output.
+ * @param tm Broken-down time to format.
+ * @return Number of bytes written.
+ */
+size_t strftime(char *restrict s, size_t maxsize,
+    const char *restrict format, const struct tm *restrict tm)
+{
+	assert(s != NULL);
+	assert(format != NULL);
+	assert(tm != NULL);
+
+	// TODO: use locale
+	static const char *wday_abbr[] = {
+		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
+	};
+	static const char *wday[] = {
+		"Sunday", "Monday", "Tuesday", "Wednesday",
+		"Thursday", "Friday", "Saturday"
+	};
+	static const char *mon_abbr[] = {
+		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+	};
+	static const char *mon[] = {
+		"January", "February", "March", "April", "May", "June", "July",
+		"August", "September", "October", "November", "December"
+	};
+	
+	if (maxsize < 1) {
+		return 0;
+	}
+	
+	char *ptr = s;
+	size_t consumed;
+	size_t remaining = maxsize;
+	
+	#define append(...) { \
+		/* FIXME: this requires POSIX-correct snprintf */ \
+		/*        otherwise it won't work with non-ascii chars */ \
+		consumed = snprintf(ptr, remaining, __VA_ARGS__); \
+		if (consumed >= remaining) { \
+			return 0; \
+		} \
+		ptr += consumed; \
+		remaining -= consumed; \
+	}
+	
+	#define recurse(fmt) { \
+		consumed = strftime(ptr, remaining, fmt, tm); \
+		if (consumed == 0) { \
+			return 0; \
+		} \
+		ptr += consumed; \
+		remaining -= consumed; \
+	}
+	
+	#define TO_12H(hour) (((hour) > 12) ? ((hour) - 12) : \
+	    (((hour) == 0) ? 12 : (hour)))
+	
+	while (*format != '\0') {
+		if (*format != '%') {
+			append("%c", *format);
+			format++;
+			continue;
+		}
+		
+		format++;
+		if (*format == '0' || *format == '+') {
+			// TODO: padding
+			format++;
+		}
+		while (isdigit(*format)) {
+			// TODO: padding
+			format++;
+		}
+		if (*format == 'O' || *format == 'E') {
+			// TODO: locale's alternative format
+			format++;
+		}
+		
+		switch (*format) {
+		case 'a':
+			append("%s", wday_abbr[tm->tm_wday]); break;
+		case 'A':
+			append("%s", wday[tm->tm_wday]); break;
+		case 'b':
+			append("%s", mon_abbr[tm->tm_mon]); break;
+		case 'B':
+			append("%s", mon[tm->tm_mon]); break;
+		case 'c':
+			// TODO: locale-specific datetime format
+			recurse("%Y-%m-%d %H:%M:%S"); break;
+		case 'C':
+			append("%02d", (1900 + tm->tm_year) / 100); break;
+		case 'd':
+			append("%02d", tm->tm_mday); break;
+		case 'D':
+			recurse("%m/%d/%y"); break;
+		case 'e':
+			append("%2d", tm->tm_mday); break;
+		case 'F':
+			recurse("%+4Y-%m-%d"); break;
+		case 'g':
+			append("%02d", _wbyear(tm) % 100); break;
+		case 'G':
+			append("%d", _wbyear(tm)); break;
+		case 'h':
+			recurse("%b"); break;
+		case 'H':
+			append("%02d", tm->tm_hour); break;
+		case 'I':
+			append("%02d", TO_12H(tm->tm_hour)); break;
+		case 'j':
+			append("%03d", tm->tm_yday); break;
+		case 'k':
+			append("%2d", tm->tm_hour); break;
+		case 'l':
+			append("%2d", TO_12H(tm->tm_hour)); break;
+		case 'm':
+			append("%02d", tm->tm_mon); break;
+		case 'M':
+			append("%02d", tm->tm_min); break;
+		case 'n':
+			append("\n"); break;
+		case 'p':
+			append("%s", tm->tm_hour < 12 ? "AM" : "PM"); break;
+		case 'P':
+			append("%s", tm->tm_hour < 12 ? "am" : "PM"); break;
+		case 'r':
+			recurse("%I:%M:%S %p"); break;
+		case 'R':
+			recurse("%H:%M"); break;
+		case 's':
+			append("%ld", _secs_since_epoch(tm)); break;
+		case 'S':
+			append("%02d", tm->tm_sec); break;
+		case 't':
+			append("\t"); break;
+		case 'T':
+			recurse("%H:%M:%S"); break;
+		case 'u':
+			append("%d", (tm->tm_wday == 0) ? 7 : tm->tm_wday);
+			break;
+		case 'U':
+			append("%02d", _sun_week_number(tm)); break;
+		case 'V':
+			append("%02d", _iso_week_number(tm)); break;
+		case 'w':
+			append("%d", tm->tm_wday); break;
+		case 'W':
+			append("%02d", _mon_week_number(tm)); break;
+		case 'x':
+			// TODO: locale-specific date format
+			recurse("%Y-%m-%d"); break;
+		case 'X':
+			// TODO: locale-specific time format
+			recurse("%H:%M:%S"); break;
+		case 'y':
+			append("%02d", tm->tm_year % 100); break;
+		case 'Y':
+			append("%d", 1900 + tm->tm_year); break;
+		case 'z':
+			// TODO: timezone
+			break;
+		case 'Z':
+			// TODO: timezone
+			break;
+		case '%':
+			append("%%");
+			break;
+		default:
+			/* Invalid specifier, print verbatim. */
+			while (*format != '%') {
+				format--;
+			}
+			append("%%");
+			break;
+		}
+		format++;
+	}
+	
+	#undef append
+	#undef recurse
+	
+	return maxsize - remaining;
+}
+
+
+/** Converts a time value to a broken-down UTC time
+ *
+ * @param time    Time to convert
+ * @param result  Structure to store the result to
+ *
+ * @return        EOK or a negative error code
+ */
+int utctime2tm(const time_t time, struct tm *restrict result)
+{
+	assert(result != NULL);
+
+	/* Set result to epoch. */
+	result->tm_sec = 0;
+	result->tm_min = 0;
+	result->tm_hour = 0;
+	result->tm_mday = 1;
+	result->tm_mon = 0;
+	result->tm_year = 70; /* 1970 */
+
+	if (_normalize_time(result, time) == -1)
+		return EOVERFLOW;
+
+	return EOK;
+}
+
+/** Converts a time value to a null terminated string of the form
+ *  "Wed Jun 30 21:49:08 1993\n" expressed in UTC.
+ *
+ * @param time   Time to convert.
+ * @param buf    Buffer to store the string to, must be at least
+ *               ASCTIME_BUF_LEN bytes long.
+ *
+ * @return       EOK or a negative error code.
+ */
+int utctime2str(const time_t time, char *restrict buf)
+{
+	struct tm t;
+	int r;
+
+	if ((r = utctime2tm(time, &t)) != EOK)
+		return r;
+
+	tm2str(&t, buf);
+	return EOK;
+}
+
+
+/**
+ * Converts broken-down time to a string in format
+ * "Sun Jan 1 00:00:00 1970\n". (Obsolete)
+ *
+ * @param timeptr Broken-down time structure.
+ * @param buf     Buffer to store string to, must be at least ASCTIME_BUF_LEN
+ *                bytes long.
+ */
+void tm2str(const struct tm *restrict timeptr, char *restrict buf)
+{
+	assert(timeptr != NULL);
+	assert(buf != NULL);
+
+	static const char *wday[] = {
+		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
+	};
+	static const char *mon[] = {
+		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+	};
+
+	snprintf(buf, ASCTIME_BUF_LEN, "%s %s %2d %02d:%02d:%02d %d\n",
+	    wday[timeptr->tm_wday],
+	    mon[timeptr->tm_mon],
+	    timeptr->tm_mday, timeptr->tm_hour,
+	    timeptr->tm_min, timeptr->tm_sec,
+	    1900 + timeptr->tm_year);
+}
+
+/**
+ * Converts a time value to a broken-down local time, expressed relative
+ * to the user's specified timezone.
+ *
+ * @param timer     Time to convert.
+ * @param result    Structure to store the result to.
+ *
+ * @return          EOK on success or a negative error code.
+ */
+int localtime2tm(const time_t time, struct tm *restrict result)
+{
+	// TODO: deal with timezone
+	// currently assumes system and all times are in GMT
+
+	/* Set result to epoch. */
+	result->tm_sec = 0;
+	result->tm_min = 0;
+	result->tm_hour = 0;
+	result->tm_mday = 1;
+	result->tm_mon = 0;
+	result->tm_year = 70; /* 1970 */
+
+	if (_normalize_time(result, time) == -1)
+		return EOVERFLOW;
+
+	return EOK;
+}
+
+/**
+ * Converts the calendar time to a null terminated string
+ * of the form "Wed Jun 30 21:49:08 1993\n" expressed relative to the
+ * user's specified timezone.
+ * 
+ * @param timer  Time to convert.
+ * @param buf    Buffer to store the string to. Must be at least
+ *               ASCTIME_BUF_LEN bytes long.
+ *
+ * @return       EOK on success or a negative error code.
+ */
+int localtime2str(const time_t time, char *buf)
+{
+	struct tm loctime;
+	int r;
+
+	if ((r = localtime2tm(time, &loctime)) != EOK)
+		return r;
+
+	tm2str(&loctime, buf);
+
+	return EOK;
+}
+
+/**
+ * Calculate the difference between two times, in seconds.
+ * 
+ * @param time1 First time.
+ * @param time0 Second time.
+ * @return Time in seconds.
+ */
+double difftime(time_t time1, time_t time0)
+{
+	return (double) (time1 - time0);
+}
+
 /** @}
  */
Index: uspace/lib/c/include/device/clock_dev.h
===================================================================
--- uspace/lib/c/include/device/clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/c/include/device/clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libc
+ * @{
+ */
+/** @file
+ */
+
+#ifndef LIBC_DEVICE_CLOCK_DEV_H_
+#define LIBC_DEVICE_CLOCK_DEV_H_
+
+#include <async.h>
+#include <time.h>
+
+typedef enum {
+	CLOCK_DEV_TIME_GET = 0,
+	CLOCK_DEV_TIME_SET,
+} clock_dev_method_t;
+
+extern int clock_dev_time_get(async_sess_t *, struct tm *);
+extern int clock_dev_time_set(async_sess_t *, struct tm *);
+
+#endif
+
Index: uspace/lib/c/include/ipc/clock_ctl.h
===================================================================
--- uspace/lib/c/include/ipc/clock_ctl.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/c/include/ipc/clock_ctl.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef LIBC_IPC_CLOCK_CTL_H_
+#define LIBC_IPC_CLOCK_CTL_H_
+
+#include <ipc/dev_iface.h>
+
+typedef enum {
+	CLOCK_GET_BATTERY_STATUS = DEV_FIRST_CUSTOM_METHOD,
+} clock_ctl_t;
+
+#endif
+
Index: uspace/lib/c/include/ipc/dev_iface.h
===================================================================
--- uspace/lib/c/include/ipc/dev_iface.h	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/include/ipc/dev_iface.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -54,4 +54,6 @@
 	/** Interface provided by USB HID devices. */
 	USBHID_DEV_IFACE,
+	/** Interface provided by Real Time Clock devices */
+	CLOCK_DEV_IFACE,
 	/** Interface provided by AHCI devices. */
 	AHCI_DEV_IFACE,
Index: uspace/lib/c/include/sys/time.h
===================================================================
--- uspace/lib/c/include/sys/time.h	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/c/include/sys/time.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -1,4 +1,6 @@
 /*
  * Copyright (c) 2006 Ondrej Palkovsky
+ * Copyright (c) 2011 Petr Koupy
+ * Copyright (c) 2011 Jiri Zarevucky
  * All rights reserved.
  *
@@ -39,4 +41,5 @@
 
 #define DST_NONE 0
+#define ASCTIME_BUF_LEN 26
 
 typedef long time_t;
@@ -45,4 +48,16 @@
 typedef uint32_t useconds_t;
 typedef uint32_t mseconds_t;
+
+struct tm {
+	int tm_sec;         /* Seconds [0,60]. */
+	int tm_min;         /* Minutes [0,59]. */
+	int tm_hour;        /* Hour [0,23]. */
+	int tm_mday;        /* Day of month [1,31]. */
+	int tm_mon;         /* Month of year [0,11]. */
+	int tm_year;        /* Years since 1900. */
+	int tm_wday;        /* Day of week [0,6] (Sunday = 0). */
+	int tm_yday;        /* Day of year [0,365]. */
+	int tm_isdst;       /* Daylight Savings flag. */
+};
 
 struct timeval {
@@ -61,6 +76,17 @@
 extern int tv_gteq(struct timeval *tv1, struct timeval *tv2);
 extern int gettimeofday(struct timeval *tv, struct timezone *tz);
+extern int getuptime(struct timeval *tv);
 
 extern void udelay(useconds_t);
+
+extern time_t mktime(struct tm *tm);
+extern int utctime2tm(const time_t time, struct tm *result);
+extern int utctime2str(const time_t time, char *buf);
+extern void tm2str(const struct tm *timeptr, char *buf);
+extern int localtime2tm(const time_t time, struct tm *result);
+extern int localtime2str(const time_t time, char *buf);
+extern double difftime(time_t time1, time_t time0);
+extern size_t strftime(char *restrict s, size_t maxsize,
+    const char *restrict format, const struct tm *restrict tm);
 
 #endif
Index: uspace/lib/drv/Makefile
===================================================================
--- uspace/lib/drv/Makefile	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/drv/Makefile	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -46,4 +46,5 @@
 	generic/remote_usbhc.c \
 	generic/remote_usbhid.c \
+	generic/remote_clock_dev.c \
 	generic/remote_ahci.c
 
Index: uspace/lib/drv/generic/dev_iface.c
===================================================================
--- uspace/lib/drv/generic/dev_iface.c	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/drv/generic/dev_iface.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -41,4 +41,5 @@
 #include "remote_hw_res.h"
 #include "remote_char_dev.h"
+#include "remote_clock_dev.h"
 #include "remote_graph_dev.h"
 #include "remote_nic.h"
@@ -59,4 +60,5 @@
 		&remote_usbhc_iface,
 		&remote_usbhid_iface,
+		&remote_clock_dev_iface,
 		&remote_ahci_iface
 	}
Index: uspace/lib/drv/generic/remote_clock_dev.c
===================================================================
--- uspace/lib/drv/generic/remote_clock_dev.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/drv/generic/remote_clock_dev.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,143 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libdrv
+ * @{
+ */
+/** @file
+ */
+
+#include <async.h>
+#include <errno.h>
+#include <time.h>
+
+#include <ops/clock_dev.h>
+#include <ddf/driver.h>
+
+static void remote_clock_time_get(ddf_fun_t *, void *, ipc_callid_t,
+    ipc_call_t *);
+static void remote_clock_time_set(ddf_fun_t *, void *, ipc_callid_t,
+    ipc_call_t *);
+
+/** Remote clock interface operations */
+static remote_iface_func_ptr_t remote_clock_dev_iface_ops[] = {
+	&remote_clock_time_get,
+	&remote_clock_time_set,
+};
+
+/** Remote clock interface structure
+ *
+ * Interface for processing requests from remote clients
+ * addressed by the clock interface.
+ */
+remote_iface_t remote_clock_dev_iface = {
+	.method_count = sizeof(remote_clock_dev_iface_ops) /
+	    sizeof(remote_iface_func_ptr_t),
+	.methods = remote_clock_dev_iface_ops,
+};
+
+/** Process the time_get() request from the remote client
+ *
+ * @param fun   The function from which the time is read
+ * @param ops   The local ops structure
+ */
+static void
+remote_clock_time_get(ddf_fun_t *fun, void *ops, ipc_callid_t callid,
+    ipc_call_t *call)
+{
+	clock_dev_ops_t *clock_dev_ops = (clock_dev_ops_t *) ops;
+	ipc_callid_t cid;
+	struct tm t;
+	int rc;
+	size_t len;
+
+	if (!async_data_read_receive(&cid, &len)) {
+		/* TODO: Handle protocol error */
+		async_answer_0(callid, EINVAL);
+		return;
+	}
+
+	if (!clock_dev_ops->time_get) {
+		/* The driver does not provide the time_get() functionality */
+		async_data_read_finalize(cid, NULL, 0);
+		async_answer_0(callid, ENOTSUP);
+		return;
+	}
+
+	rc = (*clock_dev_ops->time_get)(fun, &t);
+
+	if (rc != EOK) {
+		/* Some error occurred */
+		async_data_read_finalize(cid, NULL, 0);
+		async_answer_0(callid, rc);
+		return;
+	}
+
+	/* The operation was successful */
+	async_data_read_finalize(cid, &t, sizeof(struct tm));
+	async_answer_0(callid, rc);
+}
+
+/** Process the write request from the remote client
+ *
+ * @param fun   The function to which the data are written
+ * @param ops   The local ops structure
+ */
+static void remote_clock_time_set(ddf_fun_t *fun, void *ops,
+    ipc_callid_t callid, ipc_call_t *call)
+{
+	clock_dev_ops_t *clock_dev_ops = (clock_dev_ops_t *) ops;
+	int          rc;
+	struct tm    t;
+	ipc_callid_t cid;
+	size_t       len;
+
+	if (!async_data_write_receive(&cid, &len)) {
+		/* TODO: Handle protocol error */
+		async_answer_0(callid, EINVAL);
+		return;
+	}
+
+	if (!clock_dev_ops->time_set) {
+		/* The driver does not support the time_set() functionality */
+		async_data_write_finalize(cid, NULL, 0);
+		async_answer_0(callid, ENOTSUP);
+		return;
+	}
+
+	async_data_write_finalize(cid, &t, sizeof(struct tm));
+
+	rc = (*clock_dev_ops->time_set)(fun, &t);
+
+	async_answer_0(callid, rc);
+}
+
+/**
+ * @}
+ */
+
Index: uspace/lib/drv/include/ops/clock_dev.h
===================================================================
--- uspace/lib/drv/include/ops/clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/drv/include/ops/clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libdrv
+ * @{
+ */
+/** @file
+ */
+
+#ifndef LIBDRV_OPS_CLOCK_DEV_H_
+#define LIBDRV_OPS_CLOCK_DEV_H_
+
+#include <time.h>
+#include "../ddf/driver.h"
+
+typedef struct {
+	int (*time_get)(ddf_fun_t *, struct tm *);
+	int (*time_set)(ddf_fun_t *, struct tm *);
+} clock_dev_ops_t;
+
+#endif
+
+/**
+ * @}
+ */
Index: uspace/lib/drv/include/remote_clock_dev.h
===================================================================
--- uspace/lib/drv/include/remote_clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
+++ uspace/lib/drv/include/remote_clock_dev.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2012 Maurizio Lombardi
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libdrv
+ * @{
+ */
+/** @file
+ */
+
+#ifndef LIBDRV_REMOTE_CLOCK_DEV_H_
+#define LIBDRV_REMOTE_CLOCK_DEV_H_
+
+extern remote_iface_t remote_clock_dev_iface;
+
+#endif
+
+/**
+ * @}
+ */
+
Index: uspace/lib/posix/time.c
===================================================================
--- uspace/lib/posix/time.c	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/posix/time.c	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -61,338 +61,4 @@
  */
 
-
-
-/* Helper functions ***********************************************************/
-
-#define HOURS_PER_DAY (24)
-#define MINS_PER_HOUR (60)
-#define SECS_PER_MIN (60)
-#define MINS_PER_DAY (MINS_PER_HOUR * HOURS_PER_DAY)
-#define SECS_PER_HOUR (SECS_PER_MIN * MINS_PER_HOUR)
-#define SECS_PER_DAY (SECS_PER_HOUR * HOURS_PER_DAY)
-
-/**
- * Checks whether the year is a leap year.
- *
- * @param year Year since 1900 (e.g. for 1970, the value is 70).
- * @return true if year is a leap year, false otherwise
- */
-static bool _is_leap_year(time_t year)
-{
-	year += 1900;
-
-	if (year % 400 == 0)
-		return true;
-	if (year % 100 == 0)
-		return false;
-	if (year % 4 == 0)
-		return true;
-	return false;
-}
-
-/**
- * Returns how many days there are in the given month of the given year.
- * Note that year is only taken into account if month is February.
- *
- * @param year Year since 1900 (can be negative).
- * @param mon Month of the year. 0 for January, 11 for December.
- * @return Number of days in the specified month.
- */
-static int _days_in_month(time_t year, time_t mon)
-{
-	assert(mon >= 0 && mon <= 11);
-
-	static int month_days[] =
-		{ 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
-
-	if (mon == 1) {
-		year += 1900;
-		/* february */
-		return _is_leap_year(year) ? 29 : 28;
-	} else {
-		return month_days[mon];
-	}
-}
-
-/**
- * For specified year, month and day of month, returns which day of that year
- * it is.
- *
- * For example, given date 2011-01-03, the corresponding expression is:
- *     _day_of_year(111, 0, 3) == 2
- *
- * @param year Year (year 1900 = 0, can be negative).
- * @param mon Month (January = 0).
- * @param mday Day of month (First day is 1).
- * @return Day of year (First day is 0).
- */
-static int _day_of_year(time_t year, time_t mon, time_t mday)
-{
-	static int mdays[] =
-	    { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
-	static int leap_mdays[] =
-	    { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335 };
-
-	return (_is_leap_year(year) ? leap_mdays[mon] : mdays[mon]) + mday - 1;
-}
-
-/**
- * Integer division that rounds to negative infinity.
- * Used by some functions in this file.
- *
- * @param op1 Divident.
- * @param op2 Divisor.
- * @return Rounded quotient.
- */
-static time_t _floor_div(time_t op1, time_t op2)
-{
-	if (op1 >= 0 || op1 % op2 == 0) {
-		return op1 / op2;
-	} else {
-		return op1 / op2 - 1;
-	}
-}
-
-/**
- * Modulo that rounds to negative infinity.
- * Used by some functions in this file.
- *
- * @param op1 Divident.
- * @param op2 Divisor.
- * @return Remainder.
- */
-static time_t _floor_mod(time_t op1, time_t op2)
-{
-	int div = _floor_div(op1, op2);
-
-	/* (a / b) * b + a % b == a */
-	/* thus, a % b == a - (a / b) * b */
-
-	int result = op1 - div * op2;
-	
-	/* Some paranoid checking to ensure I didn't make a mistake here. */
-	assert(result >= 0);
-	assert(result < op2);
-	assert(div * op2 + result == op1);
-	
-	return result;
-}
-
-/**
- * Number of days since the Epoch.
- * Epoch is 1970-01-01, which is also equal to day 0.
- *
- * @param year Year (year 1900 = 0, may be negative).
- * @param mon Month (January = 0).
- * @param mday Day of month (first day = 1).
- * @return Number of days since the Epoch.
- */
-static time_t _days_since_epoch(time_t year, time_t mon, time_t mday)
-{
-	return (year - 70) * 365 + _floor_div(year - 69, 4) -
-	    _floor_div(year - 1, 100) + _floor_div(year + 299, 400) +
-	    _day_of_year(year, mon, mday);
-}
-
-/**
- * Seconds since the Epoch. see also _days_since_epoch().
- * 
- * @param tm Normalized broken-down time.
- * @return Number of seconds since the epoch, not counting leap seconds.
- */
-static time_t _secs_since_epoch(const struct posix_tm *tm)
-{
-	return _days_since_epoch(tm->tm_year, tm->tm_mon, tm->tm_mday) *
-	    SECS_PER_DAY + tm->tm_hour * SECS_PER_HOUR +
-	    tm->tm_min * SECS_PER_MIN + tm->tm_sec;
-}
-
-/**
- * Which day of week the specified date is.
- * 
- * @param year Year (year 1900 = 0).
- * @param mon Month (January = 0).
- * @param mday Day of month (first = 1).
- * @return Day of week (Sunday = 0).
- */
-static int _day_of_week(time_t year, time_t mon, time_t mday)
-{
-	/* 1970-01-01 is Thursday */
-	return _floor_mod((_days_since_epoch(year, mon, mday) + 4), 7);
-}
-
-/**
- * Normalizes the broken-down time and optionally adds specified amount of
- * seconds.
- * 
- * @param tm Broken-down time to normalize.
- * @param sec_add Seconds to add.
- * @return 0 on success, -1 on overflow
- */
-static int _normalize_time(struct posix_tm *tm, time_t sec_add)
-{
-	// TODO: DST correction
-
-	/* Set initial values. */
-	time_t sec = tm->tm_sec + sec_add;
-	time_t min = tm->tm_min;
-	time_t hour = tm->tm_hour;
-	time_t day = tm->tm_mday - 1;
-	time_t mon = tm->tm_mon;
-	time_t year = tm->tm_year;
-
-	/* Adjust time. */
-	min += _floor_div(sec, SECS_PER_MIN);
-	sec = _floor_mod(sec, SECS_PER_MIN);
-	hour += _floor_div(min, MINS_PER_HOUR);
-	min = _floor_mod(min, MINS_PER_HOUR);
-	day += _floor_div(hour, HOURS_PER_DAY);
-	hour = _floor_mod(hour, HOURS_PER_DAY);
-
-	/* Adjust month. */
-	year += _floor_div(mon, 12);
-	mon = _floor_mod(mon, 12);
-
-	/* Now the difficult part - days of month. */
-	
-	/* First, deal with whole cycles of 400 years = 146097 days. */
-	year += _floor_div(day, 146097) * 400;
-	day = _floor_mod(day, 146097);
-	
-	/* Then, go in one year steps. */
-	if (mon <= 1) {
-		/* January and February. */
-		while (day > 365) {
-			day -= _is_leap_year(year) ? 366 : 365;
-			year++;
-		}
-	} else {
-		/* Rest of the year. */
-		while (day > 365) {
-			day -= _is_leap_year(year + 1) ? 366 : 365;
-			year++;
-		}
-	}
-	
-	/* Finally, finish it off month per month. */
-	while (day >= _days_in_month(year, mon)) {
-		day -= _days_in_month(year, mon);
-		mon++;
-		if (mon >= 12) {
-			mon -= 12;
-			year++;
-		}
-	}
-	
-	/* Calculate the remaining two fields. */
-	tm->tm_yday = _day_of_year(year, mon, day + 1);
-	tm->tm_wday = _day_of_week(year, mon, day + 1);
-	
-	/* And put the values back to the struct. */
-	tm->tm_sec = (int) sec;
-	tm->tm_min = (int) min;
-	tm->tm_hour = (int) hour;
-	tm->tm_mday = (int) day + 1;
-	tm->tm_mon = (int) mon;
-	
-	/* Casts to work around libc brain-damage. */
-	if (year > ((int)INT_MAX) || year < ((int)INT_MIN)) {
-		tm->tm_year = (year < 0) ? ((int)INT_MIN) : ((int)INT_MAX);
-		return -1;
-	}
-	
-	tm->tm_year = (int) year;
-	return 0;
-}
-
-/**
- * Which day the week-based year starts on, relative to the first calendar day.
- * E.g. if the year starts on December 31st, the return value is -1.
- *
- * @param Year since 1900.
- * @return Offset of week-based year relative to calendar year.
- */
-static int _wbyear_offset(int year)
-{
-	int start_wday = _day_of_week(year, 0, 1);
-	return _floor_mod(4 - start_wday, 7) - 3;
-}
-
-/**
- * Returns week-based year of the specified time.
- *
- * @param tm Normalized broken-down time.
- * @return Week-based year.
- */
-static int _wbyear(const struct posix_tm *tm)
-{
-	int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
-	if (day < 0) {
-		/* Last week of previous year. */
-		return tm->tm_year - 1;
-	}
-	if (day > 364 + _is_leap_year(tm->tm_year)) {
-		/* First week of next year. */
-		return tm->tm_year + 1;
-	}
-	/* All the other days are in the calendar year. */
-	return tm->tm_year;
-}
-
-/**
- * Week number of the year, assuming weeks start on sunday.
- * The first Sunday of January is the first day of week 1;
- * days in the new year before this are in week 0.
- *
- * @param tm Normalized broken-down time.
- * @return The week number (0 - 53).
- */
-static int _sun_week_number(const struct posix_tm *tm)
-{
-	int first_day = (7 - _day_of_week(tm->tm_year, 0, 1)) % 7;
-	return (tm->tm_yday - first_day + 7) / 7;
-}
-
-/**
- * Week number of the year, assuming weeks start on monday.
- * If the week containing January 1st has four or more days in the new year,
- * then it is considered week 1. Otherwise, it is the last week of the previous
- * year, and the next week is week 1. Both January 4th and the first Thursday
- * of January are always in week 1.
- *
- * @param tm Normalized broken-down time.
- * @return The week number (1 - 53).
- */
-static int _iso_week_number(const struct posix_tm *tm)
-{
-	int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
-	if (day < 0) {
-		/* Last week of previous year. */
-		return 53;
-	}
-	if (day > 364 + _is_leap_year(tm->tm_year)) {
-		/* First week of next year. */
-		return 1;
-	}
-	/* All the other days give correct answer. */
-	return (day / 7 + 1);
-}
-
-/**
- * Week number of the year, assuming weeks start on monday.
- * The first Monday of January is the first day of week 1;
- * days in the new year before this are in week 0. 
- *
- * @param tm Normalized broken-down time.
- * @return The week number (0 - 53).
- */
-static int _mon_week_number(const struct posix_tm *tm)
-{
-	int first_day = (1 - _day_of_week(tm->tm_year, 0, 1)) % 7;
-	return (tm->tm_yday - first_day + 7) / 7;
-}
-
-/******************************************************************************/
-
 int posix_daylight;
 long posix_timezone;
@@ -412,47 +78,4 @@
 
 /**
- * Calculate the difference between two times, in seconds.
- * 
- * @param time1 First time.
- * @param time0 Second time.
- * @return Time in seconds.
- */
-double posix_difftime(time_t time1, time_t time0)
-{
-	return (double) (time1 - time0);
-}
-
-/**
- * This function first normalizes the provided broken-down time
- * (moves all values to their proper bounds) and then tries to
- * calculate the appropriate time_t representation.
- *
- * @param tm Broken-down time.
- * @return time_t representation of the time, undefined value on overflow.
- */
-time_t posix_mktime(struct posix_tm *tm)
-{
-	// TODO: take DST flag into account
-	// TODO: detect overflow
-
-	_normalize_time(tm, 0);
-	return _secs_since_epoch(tm);
-}
-
-/**
- * Converts a time value to a broken-down UTC time.
- *
- * @param timer Time to convert.
- * @return Normalized broken-down time in UTC, NULL on overflow.
- */
-struct posix_tm *posix_gmtime(const time_t *timer)
-{
-	assert(timer != NULL);
-
-	static struct posix_tm result;
-	return posix_gmtime_r(timer, &result);
-}
-
-/**
  * Converts a time value to a broken-down UTC time.
  * 
@@ -461,20 +84,10 @@
  * @return Value of result on success, NULL on overflow.
  */
-struct posix_tm *posix_gmtime_r(const time_t *restrict timer,
-    struct posix_tm *restrict result)
-{
-	assert(timer != NULL);
-	assert(result != NULL);
-
-	/* Set result to epoch. */
-	result->tm_sec = 0;
-	result->tm_min = 0;
-	result->tm_hour = 0;
-	result->tm_mday = 1;
-	result->tm_mon = 0;
-	result->tm_year = 70; /* 1970 */
-
-	if (_normalize_time(result, *timer) == -1) {
-		errno = EOVERFLOW;
+struct tm *posix_gmtime_r(const time_t *restrict timer,
+    struct tm *restrict result)
+{
+	int rc = utctime2tm(*timer, result);
+	if (rc != EOK) {
+		errno = rc;
 		return NULL;
 	}
@@ -484,13 +97,16 @@
 
 /**
- * Converts a time value to a broken-down local time.
- *
- * @param timer Time to convert.
- * @return Normalized broken-down time in local timezone, NULL on overflow.
- */
-struct posix_tm *posix_localtime(const time_t *timer)
-{
-	static struct posix_tm result;
-	return posix_localtime_r(timer, &result);
+ * Converts a time value to a broken-down UTC time.
+ * (non reentrant version)
+ *
+ * @param timep  Time to convert
+ * @return       Pointer to a statically allocated structure that stores
+ *               the result, NULL in case of error.
+ */
+struct tm *posix_gmtime(const time_t *restrict timep)
+{
+	static struct tm result;
+
+	return posix_gmtime_r(timep, &result);
 }
 
@@ -502,6 +118,6 @@
  * @return Value of result on success, NULL on overflow.
  */
-struct posix_tm *posix_localtime_r(const time_t *restrict timer,
-    struct posix_tm *restrict result)
+struct tm *posix_localtime_r(const time_t *restrict timer,
+    struct tm *restrict result)
 {
 	// TODO: deal with timezone
@@ -511,14 +127,16 @@
 
 /**
- * Converts broken-down time to a string in format
- * "Sun Jan 1 00:00:00 1970\n". (Obsolete)
- *
- * @param timeptr Broken-down time structure.
- * @return Pointer to a statically allocated string.
- */
-char *posix_asctime(const struct posix_tm *timeptr)
-{
-	static char buf[ASCTIME_BUF_LEN];
-	return posix_asctime_r(timeptr, buf);
+ * Converts a time value to a broken-down local time.
+ * (non reentrant version)
+ *
+ * @param timep    Time to convert.
+ * @return         Pointer to a statically allocated structure that stores
+ *                 the result, NULL in case of error.
+ */
+struct tm *posix_localtime(const time_t *restrict timep)
+{
+	static struct tm result;
+
+	return posix_localtime_r(timep, &result);
 }
 
@@ -532,250 +150,61 @@
  * @return Value of buf.
  */
-char *posix_asctime_r(const struct posix_tm *restrict timeptr,
+char *posix_asctime_r(const struct tm *restrict timeptr,
     char *restrict buf)
 {
-	assert(timeptr != NULL);
-	assert(buf != NULL);
-
-	static const char *wday[] = {
-		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
-	};
-	static const char *mon[] = {
-		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
-		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-	};
-
-	snprintf(buf, ASCTIME_BUF_LEN, "%s %s %2d %02d:%02d:%02d %d\n",
-	    wday[timeptr->tm_wday],
-	    mon[timeptr->tm_mon],
-	    timeptr->tm_mday, timeptr->tm_hour,
-	    timeptr->tm_min, timeptr->tm_sec,
-	    1900 + timeptr->tm_year);
-
+	tm2str(timeptr, buf);
 	return buf;
 }
 
 /**
- * Equivalent to asctime(localtime(clock)).
- * 
- * @param timer Time to convert.
- * @return Pointer to a statically allocated string holding the date.
- */
-char *posix_ctime(const time_t *timer)
-{
-	struct posix_tm *loctime = posix_localtime(timer);
-	if (loctime == NULL) {
-		return NULL;
-	}
-	return posix_asctime(loctime);
-}
-
-/**
- * Reentrant variant of ctime().
+ * Convers broken-down time to a string in format
+ * "Sun Jan 1 00:00:00 1970\n". (Obsolete)
+ * (non reentrant version)
+ *
+ * @param timeptr    Broken-down time structure.
+ * @return           Pointer to a statically allocated buffer that stores
+ *                   the result, NULL in case of error.
+ */
+char *posix_asctime(const struct tm *restrict timeptr)
+{
+	static char buf[ASCTIME_BUF_LEN];
+
+	return posix_asctime_r(timeptr, buf);
+}
+
+/**
+ * Converts the calendar time to a string in format
+ * "Sun Jan 1 00:00:00 1970\n" (Obsolete)
  * 
  * @param timer Time to convert.
  * @param buf Buffer to store string to. Must be at least ASCTIME_BUF_LEN
  *     bytes long.
- * @return Pointer to buf on success, NULL on falure.
+ * @return Pointer to buf on success, NULL on failure.
  */
 char *posix_ctime_r(const time_t *timer, char *buf)
 {
-	struct posix_tm loctime;
-	if (posix_localtime_r(timer, &loctime) == NULL) {
+	int r = localtime2str(*timer, buf);
+	if (r != EOK) {
+		errno = r;
 		return NULL;
 	}
-	return posix_asctime_r(&loctime, buf);
-}
-
-/**
- * Convert time and date to a string, based on a specified format and
- * current locale.
- * 
- * @param s Buffer to write string to.
- * @param maxsize Size of the buffer.
- * @param format Format of the output.
- * @param tm Broken-down time to format.
- * @return Number of bytes written.
- */
-size_t posix_strftime(char *restrict s, size_t maxsize,
-    const char *restrict format, const struct posix_tm *restrict tm)
-{
-	assert(s != NULL);
-	assert(format != NULL);
-	assert(tm != NULL);
-
-	// TODO: use locale
-	static const char *wday_abbr[] = {
-		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
-	};
-	static const char *wday[] = {
-		"Sunday", "Monday", "Tuesday", "Wednesday",
-		"Thursday", "Friday", "Saturday"
-	};
-	static const char *mon_abbr[] = {
-		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
-		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-	};
-	static const char *mon[] = {
-		"January", "February", "March", "April", "May", "June", "July",
-		"August", "September", "October", "November", "December"
-	};
-	
-	if (maxsize < 1) {
-		return 0;
-	}
-	
-	char *ptr = s;
-	size_t consumed;
-	size_t remaining = maxsize;
-	
-	#define append(...) { \
-		/* FIXME: this requires POSIX-correct snprintf */ \
-		/*        otherwise it won't work with non-ascii chars */ \
-		consumed = snprintf(ptr, remaining, __VA_ARGS__); \
-		if (consumed >= remaining) { \
-			return 0; \
-		} \
-		ptr += consumed; \
-		remaining -= consumed; \
-	}
-	
-	#define recurse(fmt) { \
-		consumed = posix_strftime(ptr, remaining, fmt, tm); \
-		if (consumed == 0) { \
-			return 0; \
-		} \
-		ptr += consumed; \
-		remaining -= consumed; \
-	}
-	
-	#define TO_12H(hour) (((hour) > 12) ? ((hour) - 12) : \
-	    (((hour) == 0) ? 12 : (hour)))
-	
-	while (*format != '\0') {
-		if (*format != '%') {
-			append("%c", *format);
-			format++;
-			continue;
-		}
-		
-		format++;
-		if (*format == '0' || *format == '+') {
-			// TODO: padding
-			format++;
-		}
-		while (isdigit(*format)) {
-			// TODO: padding
-			format++;
-		}
-		if (*format == 'O' || *format == 'E') {
-			// TODO: locale's alternative format
-			format++;
-		}
-		
-		switch (*format) {
-		case 'a':
-			append("%s", wday_abbr[tm->tm_wday]); break;
-		case 'A':
-			append("%s", wday[tm->tm_wday]); break;
-		case 'b':
-			append("%s", mon_abbr[tm->tm_mon]); break;
-		case 'B':
-			append("%s", mon[tm->tm_mon]); break;
-		case 'c':
-			// TODO: locale-specific datetime format
-			recurse("%Y-%m-%d %H:%M:%S"); break;
-		case 'C':
-			append("%02d", (1900 + tm->tm_year) / 100); break;
-		case 'd':
-			append("%02d", tm->tm_mday); break;
-		case 'D':
-			recurse("%m/%d/%y"); break;
-		case 'e':
-			append("%2d", tm->tm_mday); break;
-		case 'F':
-			recurse("%+4Y-%m-%d"); break;
-		case 'g':
-			append("%02d", _wbyear(tm) % 100); break;
-		case 'G':
-			append("%d", _wbyear(tm)); break;
-		case 'h':
-			recurse("%b"); break;
-		case 'H':
-			append("%02d", tm->tm_hour); break;
-		case 'I':
-			append("%02d", TO_12H(tm->tm_hour)); break;
-		case 'j':
-			append("%03d", tm->tm_yday); break;
-		case 'k':
-			append("%2d", tm->tm_hour); break;
-		case 'l':
-			append("%2d", TO_12H(tm->tm_hour)); break;
-		case 'm':
-			append("%02d", tm->tm_mon); break;
-		case 'M':
-			append("%02d", tm->tm_min); break;
-		case 'n':
-			append("\n"); break;
-		case 'p':
-			append("%s", tm->tm_hour < 12 ? "AM" : "PM"); break;
-		case 'P':
-			append("%s", tm->tm_hour < 12 ? "am" : "PM"); break;
-		case 'r':
-			recurse("%I:%M:%S %p"); break;
-		case 'R':
-			recurse("%H:%M"); break;
-		case 's':
-			append("%ld", _secs_since_epoch(tm)); break;
-		case 'S':
-			append("%02d", tm->tm_sec); break;
-		case 't':
-			append("\t"); break;
-		case 'T':
-			recurse("%H:%M:%S"); break;
-		case 'u':
-			append("%d", (tm->tm_wday == 0) ? 7 : tm->tm_wday); break;
-		case 'U':
-			append("%02d", _sun_week_number(tm)); break;
-		case 'V':
-			append("%02d", _iso_week_number(tm)); break;
-		case 'w':
-			append("%d", tm->tm_wday); break;
-		case 'W':
-			append("%02d", _mon_week_number(tm)); break;
-		case 'x':
-			// TODO: locale-specific date format
-			recurse("%Y-%m-%d"); break;
-		case 'X':
-			// TODO: locale-specific time format
-			recurse("%H:%M:%S"); break;
-		case 'y':
-			append("%02d", tm->tm_year % 100); break;
-		case 'Y':
-			append("%d", 1900 + tm->tm_year); break;
-		case 'z':
-			// TODO: timezone
-			break;
-		case 'Z':
-			// TODO: timezone
-			break;
-		case '%':
-			append("%%");
-			break;
-		default:
-			/* Invalid specifier, print verbatim. */
-			while (*format != '%') {
-				format--;
-			}
-			append("%%");
-			break;
-		}
-		format++;
-	}
-	
-	#undef append
-	#undef recurse
-	
-	return maxsize - remaining;
+
+	return buf;
+}
+
+/**
+ * Converts the calendar time to a string in format
+ * "Sun Jan 1 00:00:00 1970\n" (Obsolete)
+ * (non reentrant version)
+ *
+ * @param timep    Time to convert.
+ * @return         Pointer to a statically allocated buffer that stores
+ *                 the result, NULL in case of error.
+ */
+char *posix_ctime(const time_t *timep)
+{
+	static char buf[ASCTIME_BUF_LEN];
+
+	return posix_ctime_r(timep, buf);
 }
 
@@ -894,5 +323,6 @@
 	stats_task_t *task_stats = stats_get_task(task_get_id());
 	if (task_stats) {
-		total_cycles = (posix_clock_t) (task_stats->kcycles + task_stats->ucycles);
+		total_cycles = (posix_clock_t) (task_stats->kcycles +
+		    task_stats->ucycles);
 		free(task_stats);
 		task_stats = 0;
Index: uspace/lib/posix/time.h
===================================================================
--- uspace/lib/posix/time.h	(revision 111d2d6731b1fbc5a2181c92094ca7b8dbaf9d2f)
+++ uspace/lib/posix/time.h	(revision 762083bc8a2d6259a231487a7f1d20a786ff0a6b)
@@ -63,21 +63,6 @@
 #endif
 
-#undef ASCTIME_BUF_LEN
-#define ASCTIME_BUF_LEN 26
-
 #undef CLOCK_REALTIME
 #define CLOCK_REALTIME ((posix_clockid_t) 0)
-
-struct posix_tm {
-	int tm_sec;         /* Seconds [0,60]. */
-	int tm_min;         /* Minutes [0,59]. */
-	int tm_hour;        /* Hour [0,23]. */
-	int tm_mday;        /* Day of month [1,31]. */
-	int tm_mon;         /* Month of year [0,11]. */
-	int tm_year;        /* Years since 1900. */
-	int tm_wday;        /* Day of week [0,6] (Sunday = 0). */
-	int tm_yday;        /* Day of year [0,365]. */
-	int tm_isdst;       /* Daylight Savings flag. */
-};
 
 struct posix_timespec {
@@ -99,24 +84,18 @@
 extern void posix_tzset(void);
 
-/* Elapsed Time */
-extern double posix_difftime(time_t time1, time_t time0);
-
 /* Broken-down Time */
-extern time_t posix_mktime(struct posix_tm *tm);
-extern struct posix_tm *posix_gmtime(const time_t *timer);
-extern struct posix_tm *posix_gmtime_r(const time_t *restrict timer,
-    struct posix_tm *restrict result);
-extern struct posix_tm *posix_localtime(const time_t *timer);
-extern struct posix_tm *posix_localtime_r(const time_t *restrict timer,
-    struct posix_tm *restrict result);
+extern struct tm *posix_gmtime_r(const time_t *restrict timer,
+    struct tm *restrict result);
+extern struct tm *posix_gmtime(const time_t *restrict timep);
+extern struct tm *posix_localtime_r(const time_t *restrict timer,
+    struct tm *restrict result);
+extern struct tm *posix_localtime(const time_t *restrict timep);
 
 /* Formatting Calendar Time */
-extern char *posix_asctime(const struct posix_tm *timeptr);
-extern char *posix_asctime_r(const struct posix_tm *restrict timeptr,
+extern char *posix_asctime_r(const struct tm *restrict timeptr,
     char *restrict buf);
+extern char *posix_asctime(const struct tm *restrict timeptr);
+extern char *posix_ctime_r(const time_t *timer, char *buf);
 extern char *posix_ctime(const time_t *timer);
-extern char *posix_ctime_r(const time_t *timer, char *buf);
-extern size_t posix_strftime(char *restrict s, size_t maxsize,
-    const char *restrict format, const struct posix_tm *restrict tm);
 
 /* Clocks */
@@ -134,27 +113,22 @@
 
 #ifndef LIBPOSIX_INTERNAL
-	#define tm posix_tm
-	#define timespec posix_timespec
-	#define itimerspec posix_itimerspec
-	#define timer_t posix_timer_t
+	#define timespec    posix_timespec
+	#define itimerspec  posix_itimerspec
+	#define timer_t     posix_timer_t
 
-	#define daylight posix_daylight
-	#define timezone posix_timezone
-	#define tzname posix_tzname
-	#define tzset posix_tzset
+	#define daylight    posix_daylight
+	#define timezone    posix_timezone
+	#define tzname      posix_tzname
+	#define tzset       posix_tzset
 
-	#define difftime posix_difftime
+	#define gmtime_r    posix_gmtime_r
+	#define gmtime      posix_gmtime
+	#define localtime_r posix_localtime_r
+	#define localtime   posix_localtime
 
-	#define mktime posix_mktime
-	#define gmtime posix_gmtime
-	#define gmtime_r posix_gmtime_r
-	#define localtime posix_localtime
-	#define localtime_r posix_localtime_r
-
-	#define asctime posix_asctime
-	#define asctime_r posix_asctime_r
-	#define ctime posix_ctime
-	#define ctime_r posix_ctime_r
-	#define strftime posix_strftime
+	#define asctime_r   posix_asctime_r
+	#define asctime     posix_asctime
+	#define ctime_r     posix_ctime_r
+	#define ctime       posix_ctime
 
 	#define clock_getres posix_clock_getres
