Proposing the macro variable name "_CLIENTTASKLASTRUN", such would be inserted in to the code like so. (How it would look in a program node log":
1 ;*';*";*/;quit;run;
2 OPTIONS PAGENO=MIN;
3 %LET _CLIENTTASKLABEL='LIBNAMES';
4 %LET _CLIENTTASKLASTRUN='17OCT1991/14:45:32';
5 %LET _CLIENTPROCESSFLOWNAME='Logs';
...
If the node has not been ran yet, last-run date would be null, and therefore...
...
4 %LET _CLIENTTASKLASTRUN='.';
...