.p4ignore is our collected catch all ignore file that we use for our UE projects
The other corresponding *.p4ignore files are snippets for each individual program.
To use these files, first check that you do not have any existing P4IGNORE environment variable set by running:
p4 set
in command prompt to view your existing environment variables.
To set the value to use the .p4ignore file, enter the following in your command prompt:
p4 set P4IGNORE=.p4ignore