deanm0000 commented on issue #160:
URL: https://github.com/apache/avro-rs/issues/160#issuecomment-2736970011

   Thanks for the response. I just tried it out and I got it to work (I think) 
but I'm a bit confused how the marker works and not sure if I'm doing it right. 
I inferred from 
[this](https://github.com/apache/avro-rs/blob/c1c595a053d46f354102a3b4628d3c8600140307/avro/src/reader.rs#L598)
 that it's just the last 16 bytes of the file so I made this function to get 
the schema and marker
   
   ```rust
   fn get_schema_marker(file: &File) -> (Schema, [u8; 16]) {
       let mut fs_reader = BufReader::new(file);
       fs_reader
           .seek(SeekFrom::End(-16))
           .expect("couldn't seek to end");
       let mut buffer = [0u8; 16];
       fs_reader
           .read_exact(&mut buffer)
           .expect("couldn't read exact");
       fs_reader
           .seek(SeekFrom::Start(0))
           .expect("couldn't seek to start");
       let reader = Reader::new(fs_reader).unwrap();
       let schema = reader.writer_schema().clone();
       (schema, buffer)
   }
   ```
   
   and then this one to append
   
   ```rust
   fn append_avro(test_file: &str) {
       let f = OpenOptions::new()
           .append(true)
           .read(true)
           .open(test_file)
           .expect("Unable to open file in append");
       let (schema, marker) = get_schema_marker(&f);
   
       let mut writer = Writer::append_to(&schema, BufWriter::new(f), marker);
       let mut record = Record::new(&schema).unwrap();
       record.put("field1", "goodbye");
       writer.append(record).unwrap();
       writer.into_inner().expect("failed append writer.into");
   }
   ```
   
   Do those make sense in a file context or is there anything glaringly wrong 
and/or unnecessary? 


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