Get file inode during the file change owner in HDFS Hadoop?

how to get file INode in active file? for example:
under client type command as below:
./hadoop fs -chown -R hadoop:hadoop hdfs://nn:9000/A1.txt
how to get "A1.txt" file INode during the file change owner operation?
or  let me change a way to say:
How do I get the pointer to the active file inode if I want to add something to the file inode?
Thanks!