diff --git a/libs/main/core/pibinarystream.h b/libs/main/core/pibinarystream.h
index 02c3635c..16c2839b 100644
--- a/libs/main/core/pibinarystream.h
+++ b/libs/main/core/pibinarystream.h
@@ -40,11 +40,23 @@ class PIBinaryStream {
 public:
 	// one should implements next methods:
 	//
-	// void appendImp(const void * d, size_t s);
-	// void takeImp(void * d, size_t s);
+	// bool binaryStreamAppend(const void * d, size_t s);
+	// bool binaryStreamTake(void * d, size_t s);
 
-	void append(const void * d, size_t s) {static_cast<P*>(this)->appendImp(d, s);}
-	void take(void * d, size_t s) {static_cast<P*>(this)->takeImp(d, s);}
+	bool append(const void * d, size_t s) {
+		if (!static_cast<P*>(this)->binaryStreamAppend(d, s)) {
+			return false;
+			printf("[PIBinaryStream] append() error\n");
+		}
+		return true;
+	}
+	bool take(void * d, size_t s) {
+		if (!static_cast<P*>(this)->binaryStreamTake(d, s)) {
+			return false;
+			printf("[PIBinaryStream] take() error\n");
+		}
+		return true;
+	}
 	template<typename T>
 	void append(T v) {append(&v, sizeof(v));}
 	uchar takeByte() {uchar r = 0; take(&r, sizeof(r)); return r;}
@@ -173,7 +185,10 @@ inline PIBinaryStream<P> & operator <<(PIBinaryStream<P> & s, const PIPair<Type0
 
 template<typename P, typename T, typename std::enable_if< std::is_trivially_copyable<T>::value, int>::type = 0>
 inline PIBinaryStreamRef<P> operator >>(PIBinaryStream<P> & s, T & v) {
-	s.take(&v, sizeof(v));
+	if (!s.take(&v, sizeof(v))) {
+		printf("error with %s\n", __PIP_TYPENAME__(T));
+		assert(false);
+	}
 	return s;
 }
 
@@ -187,7 +202,10 @@ inline PIBinaryStream<P> & operator >>(PIBinaryStream<P> & s, PIVector<T> & v) {
 	piCout << ">> vector trivial default";
 	int sz = s.takeInt();
 	v._resizeRaw(sz);
-	s.take(v.data(), sz*sizeof(T));
+	if (!s.take(v.data(), sz * sizeof(T))) {
+		printf("error with PIVector<%s>\n", __PIP_TYPENAME__(T));
+		assert(false);
+	}
 	return s;
 }
 template<typename P, typename T,
@@ -211,7 +229,10 @@ inline PIBinaryStream<P> & operator >>(PIBinaryStream<P> & s, PIDeque<T> & v) {
 	piCout << ">> deque trivial default";
 	int sz = s.takeInt();
 	v._resizeRaw(sz);
-	s.take(v.data(), sz*sizeof(T));
+	if (!s.take(v.data(), sz * sizeof(T))) {
+		printf("error with PIDeque<%s>\n", __PIP_TYPENAME__(T));
+		assert(false);
+	}
 	return s;
 }
 template<typename P, typename T,
@@ -237,7 +258,10 @@ inline PIBinaryStream<P> & operator >>(PIBinaryStream<P> & s, PIVector2D<T> & v)
 	r = s.takeInt();
 	c = s.takeInt();
 	v._resizeRaw(r, c);
-	s.take(v.data(), v.size() * sizeof(T));
+	if (!s.take(v.data(), v.size() * sizeof(T))) {
+		printf("error with PIVector2D<%s>\n", __PIP_TYPENAME__(T));
+		assert(false);
+	}
 	return s;
 }
 template<typename P, typename T,
diff --git a/main.cpp b/main.cpp
index 52ca5804..f9e77a5b 100644
--- a/main.cpp
+++ b/main.cpp
@@ -9,32 +9,40 @@ using namespace PICoutManipulators;
 class ByteArray: public PIBinaryStream<ByteArray> {
 public:
 	PIByteArray data;
-	void appendImp(const void * d, size_t s) {
+	bool binaryStreamAppend(const void * d, size_t s) {
 		data.append(d, s);
+		return true;
 	}
-	void takeImp(void * d, size_t s) {
+	bool binaryStreamTake(void * d, size_t s) {
+		if (data.size() < s)
+			return false;
 		memcpy(d, data.data(), s);
 		data.remove(0, s);
+		return true;
 	}
 };
 
 class File: public PIBinaryStream<File> {
 public:
 	PIFile file;
-	void appendImp(const void * d, size_t s) {
+	bool binaryStreamAppend(const void * d, size_t s) {
 		file.write(d, s);
+		return true;
 	}
-	void takeImp(void * d, size_t s) {
+	bool binaryStreamTake(void * d, size_t s) {
+		if (file.isEnd())
+			return false;
 		file.read(d, s);
+		return true;
 	}
 };
 
 
 struct TS {
-	TS(int v0 = -1, float v1 = -1, PIString v2 = "") {i = v0; f = v1; s = v2;}
+	TS(int v0 = -1, float v1 = -1, PIString v2 = "") {i = v0; f = v1;/* s = v2;*/}
 	int i;
 	float f;
-	PIString s;
+	//PIString s;
 };
 PICout operator << (PICout c, const TS & v) {c << '{' << v.i << ", " << v.f << '}'; return c;}
 
@@ -50,11 +58,11 @@ int main(int argc, char * argv[]) {
 	//f.file.open("_", PIIODevice::ReadWrite);
 	//f.file.clear();
 	//PIVector<TS> vi({TS(1,20), TS(3,40)});
-	PIVector<PIChar> vi({'a', 'b', 'c'});
+	PIVector<TS> vi({{'a', 10}, {'b', 20}, {'c', 30}});
 	ba << vi;
 	piCout << "src" << vi;
 	piCout << "s" << ba.data;
-	vi.fill(' ');
+	vi.fill(TS());
 	vi.clear();
 	//f.file.seekToBegin();
 	ba >> vi;