Gateway files are created in the directory where the Gateway binary (e.g. gateway2.linux) has been executed.
Some examples of the Gateway files:
licences.cache - It contains the license info. In case there is a disconnection to license daemon, the gateway can continue function.
cache - cache folder for the Gateway process
lib64 - library files the Gateway requires
gateway.user_assignment - user assignment data file
gateway.snooze - file contains info of snoozed items