diff --git a/c/timeconv_test/Makefile b/c/timeconv_test/Makefile
new file mode 100644
index 0000000..d7eedc4
--- /dev/null
+++ b/c/timeconv_test/Makefile
@@ -0,0 +1,108 @@
+# This file is generated with smake.sh.
+# You can use this make file with instruction make to
+# use one of build mode: debug, profile, develop, release.
+# No need to call make clean if You make with other mode,
+# because the Makefile containes rules for automatically clean.
+# Some usage examples:
+# make # default mode is debug
+# CFLAGS="-O2 -march=core2 -mtune=core2 --msse4.1 mfpmath=sse -fomit-frame-pointer -pipe" LDFLAGS="-Wl,-O1 -Wl,-ass-needed" make mode=develop
+# CFLAGS="-O2 -march=amdfam10 -mtune=amdfam10 -msse4a --mfpmath=sse -fomit-frame-pointer -pipe" LDFLAGS="-Wl,-O1 -Wl,--as-needed" make mode=profile
+# CFLAGS="-O2 -march=k6-2 -mtune=k6-2 -m3dnow --mfpmath=387 -fomit-frame-pointer -pipe" LDFLAGS="-Wl,-O1 -Wl,--as-needed" make mode=release
+# Report bugs to <mecareful@gmail.com>
+
+#_________________________________
+#          ENVIRONMENT           |
+#________________________________|
+CC=cc
+CXX=c++
+LIBRARIES=
+TARGET0=timeconv_test
+TARGET= $(TARGET0)
+INCLUDE1=$(HOME)/projects/include
+INCLUDE2=/usr/local/include
+INCLUDE=-I$(INCLUDE1) -I$(INCLUDE2)
+
+#________________________________________
+#      BUILD SCRIPT (don't change)      |
+#_______________________________________|
+ifeq ($(mode),)
+	mode = debug
+endif
+ifeq ($(mode),debug)
+	CFLAGS := -O0 -g -std=gnu99 -pedantic -Wextra -Wconversion $(CFLAGS)
+	LDFLAGS := $(LDFLAGS)
+endif
+ifeq ($(mode),profile)
+	CFLAGS := -O0 -g -p -ftest-coverage -Wcoverage-mismatch $(CFLAGS)
+	LDFLAGS := -g -p $(LDFLAGS)
+endif
+ifeq ($(mode),develop)
+	CFLAGS := -O2 -g $(CFLAGS)
+	LDFLAGS := -O1 $(LDFLAGS)
+endif
+ifeq ($(mode),release)
+	CFLAGS := -O2 $(CFLAGS)
+	LDFLAGS := -O1 $(LDFLAGS)
+endif
+
+CFLAGS += -Wall
+LDFLAGS += -Wall $(LIBRARIES)
+
+all: change_make_options $(TARGET)
+
+ifneq ($(mode),debug)
+ifneq ($(mode),profile)
+ifneq ($(mode),develop)
+ifneq ($(mode),release)
+	@echo "Invalid build mode."
+	@echo "Please use 'make mode=release', 'make mode=develop', 'make mode=profile' or 'make mode=debug'"
+	@exit 1
+endif
+endif
+endif
+endif
+	@echo ".........................."
+	@echo "Building on "$(mode)" mode "
+	@echo "CFLAGS=$(CFLAGS)"
+	@echo "LDFLAGS=$(LDFLAGS)"
+	@echo ".........................."
+
+OLD_BUILD_MODE=$(shell grep ^MODE make_options.out 2>/dev/null | sed 's~^MODE=~~')
+OLD_BUILD_CFLAGS=$(shell grep ^CFLAGS make_options.out 2>/dev/null | sed 's~^CFLAGS=~~')
+OLD_BUILD_LDFLAGS=$(shell grep ^LDFLAGS make_options.out 2>/dev/null | sed 's~^LDFLAGS=~~')
+change_make_options:
+ifneq ($(mode)|$(CFLAGS)|$(LDFLAGS), $(OLD_BUILD_MODE)|$(OLD_BUILD_CFLAGS)|$(OLD_BUILD_LDFLAGS))
+	@echo CLEANING...
+	@make clean &>/dev/null
+	@echo "MODE=$(mode)" > make_options.out
+	@echo "CFLAGS=$(CFLAGS)" >> make_options.out
+	@echo "LDFLAGS=$(LDFLAGS)" >> make_options.out
+endif
+
+%.o :
+	$(CC) -c $(CFLAGS) $(INCLUDE) -o $@ $<
+
+clean:
+	$(RM) *.o *.out callgrind.out.* *.gcno $(TARGET)
+
+.PHONY: all change_make_options clean
+
+#_________________________________
+#           R U L E S            |
+#________________________________|
+target_objs0 = \
+	timeconv_test.o \
+	timeconv.o
+
+$(TARGET0): $(target_objs0)
+	$(CC) $(LDFLAGS) -o $@ $(target_objs0)
+
+
+timeconv_test.o: \
+	timeconv_test.c \
+	$(INCLUDE1)/timeconv.h
+
+timeconv.o: \
+	$(INCLUDE1)/timeconv.c \
+	$(INCLUDE1)/timeconv.h
+
diff --git a/c/timeconv_test/timeconv_test.c b/c/timeconv_test/timeconv_test.c
new file mode 100644
index 0000000..d3ab285
--- /dev/null
+++ b/c/timeconv_test/timeconv_test.c
@@ -0,0 +1,48 @@
+#include <time.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "timeconv.h"
+
+void usec_test()
+{
+	struct tm t;
+	struct timeval tv;
+	uint64_t usec = 0;
+	char buf[256];
+
+	putenv("TZ=GMT+0");
+
+	t.tm_sec = 1;
+	t.tm_min = 2;
+	t.tm_hour = 3;
+	t.tm_mday = 4;
+	t.tm_mon = 5-1;
+	t.tm_year = 2011-1900;
+	t.tm_isdst = 0;
+
+	tv.tv_sec = mktime(&t);
+	tv.tv_usec = 798431;
+
+	usec = usec_from_timeval(tv);
+
+	memset(&tv, 0, sizeof(tv));
+
+	tv = timeval_from_usec(usec);
+
+	memset(&t, 0, sizeof(t));
+
+	t = *gmtime(&tv.tv_sec);
+
+	strftime(buf, sizeof(buf), "%Y.%m.%d %H:%M:%S", &t);
+	printf("%s\n", buf);
+}
+
+int main(int argc, char *argv[])
+{
+	usec_test();
+
+	return 0;
+}
+