It's a relative path to user.dir. So it depends on where the JVM is launched. There is no way to override. Any tool that wants to use zanata client commands to do the pulling will be left with no choice. e.g. if Zanata Sync is trying to run multiple PullCommand threads from within a JBoss process, they will all write to jboss home.
To implement: a new argument in Zanata client to define the zanata cache file location.