You should be having a table with the list of groups, otherwise create a cursor with columns Emname and Irsrc and populate it with all the records you need. Then join that group table with the summary cursor
SELECT CUNION.Emname, CUNION.Irsrc, SUM(CUNION.Cnt_irsrc) as Totals;
FROM 'CUNION.DBF' CUNION;
GROUP BY CUNION.Emname, CUNION.Irsrc;
ORDER BY CUNION.Emname, CUNION.Irsrc;
INTO CURSOR SummaryCursor
SELECT MyGroupTable.EmName, MyGroupTable.Irsrc,NVL(SummaryCursor.Totals,0) as Totals ;
from MyGroupTable ;
LEFT JOIN SummaryCursor ON MyGroupTable.EmName=SummaryCursor.EmName and MyGroupTable.Irsrc=SummaryCursor.Irsrc;
INTO CURSOR SummaryCursor1