Corrections to the method write_to in C Api

Signed-off-by: UpeksheJay <usmj000@gmail.com>

ext/nio4r/bytebuffer.c

@@ -205,7 +205,10 @@ static VALUE NIO_ByteBuffer_writeTo(VALUE self, VALUE io){
     GetOpenFile(rb_convert_type(io, T_FILE, "IO", "to_io"), fptr);
     rb_io_set_nonblock(fptr);
 
-	write(FPTR_TO_FD(fptr), StringValuePtr(NIO_ByteBuffer_get(self)), size);
+    VALUE content = NIO_ByteBuffer_get(self);
+    char* contentAsPointer = StringValuePtr(content);
+
+	write(FPTR_TO_FD(fptr), contentAsPointer , size);
 
     return self;
 }
@@ -215,8 +218,6 @@ static VALUE NIO_ByteBuffer_readFrom(VALUE self, VALUE file){
 	Data_Get_Struct(self, struct NIO_ByteBuffer, byteBuffer);
 	int size = byteBuffer->limit + 1 - byteBuffer->position;
 
-	//Still not complete...
-
     return self;
 }