UPDATE
m4_if([$1], [sav], [FILE='a.sav'], [FILE=*]) /IN=InA /SORT
m4_if([$2], [sav], [FILE='b.sav'], [FILE=*]) /IN=InB /RENAME c=d
UPDATE
m4_if([$1], [sav], [FILE='a.sav'], [FILE=*]) /IN=InA /SORT
m4_if([$2], [sav], [FILE='b.sav'], [FILE=*]) /IN=InB /RENAME c=d