projid(5) File Formats Manual projid(5)

projid - the project name mapping file

The /etc/projid file provides a mapping between numeric project identifiers and a simple human readable name (similar relationship to the one that exists between usernames and uids). Its format is simply:

# comments are hash-prefixed
# ...
cage:10
logfiles:42

This file is optional, if a project identifier cannot be mapped to a name, it will be parsed and displayed as a numeric value.

xfs_quota(8), xfsctl(3), projects(5).