hdfs file "start time" in org.apache.solr.hadoop.HdfsFindTool

[#1]

on this guide: https://www.cloudera.com/documentation/enterprise/5-3-x/topics/search_hdfsfindtool.html

there is a reference in the -mtime option:

Evaluates as true if the file modification time subtracted


    from the start time is n days

what does the "start time"  in here reference?

it does not seem to work like normal bash find.

i want functionality like:

if mtime is more than 30 days ago (from current time), print the folder/file.