Swift Using shell variables
Any value in swift.properties may contain environment variables. For example:
workdir=/scratch/midway/$USER/work
Environment variables are expanded locally on the machine where you are running Swift.
Swift will also define a variable called $RUNDIRECTORY that is the path to the run directory Swift creates. In a case where you’d like your work directory to be in the runNNN directory, you may do something like this:
workdir=$RUNDIRECTORY