write data in append mode

Hi experts,
I am trying to write some sample code using the usrbio library. But when I write a simple "write" code, looks like it's always overwriting the target file. Is there anything else I need to do besides getting a FD in the append mode in order to append to a file?

Thanks!

Start by locating the usrbio implementation and its handling of file descriptors opened in append mode. Reproduce the reported write behavior with a sample file, then compare the observed result with the expected append semantics; done means existing file contents are preserved and new data is added.

Written by the indexing model from the issue text.