FST: Use eval command for correct variable substitution in datadistribution.sh

Author: davidrohr

prodtests/full-system-test/datadistribution.sh

@@ -34,7 +34,7 @@ export TFRATE=$(awk "BEGIN {printf \"%.6f\",1/$TFDELAY}")
 
 ARGS_ALL="--session default --severity $SEVERITY --shm-segment-id 2 --shm-segment-size 1000000 --no-cleanup"
 
-StfBuilder --id stfb --transport shmem \
+eval StfBuilder --id stfb --transport shmem \
   --dpl-channel-name dpl-chan --channel-config "name=dpl-chan,type=push,method=bind,address=ipc://@$INRAWCHANNAME,transport=shmem,rateLogging=1" \
   $DD_INPUT_CMD \
   --data-source-rate=${TFRATE} \