diff --git a/Makefile b/Makefile
index 348cdaa397..5f90fe6a5b 100644
--- a/Makefile
+++ b/Makefile
@@ -539,7 +539,7 @@ clean:
 	$(MAKE) -C stdtime clean
 
 datafiles: all
-	if [ x`whoami` = xroot ]; then sh mkpkgconfig $(DESTDIR)/usr/lib/pkgconfig; fi
+	if [ x`id -un` = xroot ]; then sh mkpkgconfig $(DESTDIR)/usr/lib/pkgconfig; fi
 	mkdir -p $(DESTDIR)$(ASTVARLIBDIR)/sounds/digits
 	mkdir -p $(DESTDIR)$(ASTVARLIBDIR)/sounds/priv-callerintros
 	for x in sounds/digits/*.gsm; do \