diff --git a/src/memstreambuf.cpp b/src/memstreambuf.cpp
index d24c87b..61ec8c8 100644
--- a/src/memstreambuf.cpp
+++ b/src/memstreambuf.cpp
@@ -54,24 +54,25 @@ std::streamsize sc::io::memstreambuf::xsputn(const char* /*s*/, std::streamsize
 std::streambuf::pos_type sc::io::memstreambuf::seekoff(std::streambuf::off_type off,
 													   std::ios_base::seekdir dir,
 													   std::ios_base::openmode which) {
+	uint64_t pos {0};
 	if (which & std::ios::in) { // reading
 		switch (dir) {
 			case std::ios::beg:
 				if (off < 0 || static_cast<size_t>(off) > _size) return EOF;
-				setg(_mem, _mem + off, _mem + _size);
+				pos = off;
 				break;
 			case std::ios::cur: {
-				int64_t pos = gptr() - _mem + off;
-				if (pos < 0 || static_cast<size_t>(pos) > _size) return EOF;
-				setg(_mem, gptr() + off, _mem + _size);
+				int64_t spos = gptr() - _mem + off;
+				if (spos < 0 || static_cast<size_t>(spos) > _size) return EOF;
+				pos = static_cast<uint64_t>(spos);
 				break;
 			}
 			case std::ios::end:
-				if (off > 0 || static_cast<size_t>(off) < -_size) return EOF;
-				setg(_mem, _mem + _size + off - 1, _mem + _size);
+				if (off > 0 || static_cast<std::streambuf::off_type>(_size) < -off) return EOF;
+				pos = _size + off - 1;
 				break;
 		}
-		return gptr() - _mem;
+		setg(_mem, _mem + pos, _mem + _size);
 	}
 	if (which & std::ios::out) { // writing
 		switch (dir) { // TODO
@@ -82,9 +83,8 @@ std::streambuf::pos_type sc::io::memstreambuf::seekoff(std::streambuf::off_type
 			case std::ios::end:
 				break;
 		}
-		return pptr() - _mem;
 	}
-	return EOF;
+	return pos;
 }
 
 std::streambuf::pos_type sc::io::memstreambuf::seekpos(std::streambuf::pos_type pos,