diff --git a/test/gidmapping.sh b/test/gidmapping.sh
index 1415bbc8..1dcc933a 100755
--- a/test/gidmapping.sh
+++ b/test/gidmapping.sh
@@ -3,8 +3,8 @@
 TRY_TOP="${TRY_TOP:-$(git rev-parse --show-toplevel --show-superproject-working-tree)}"
 TRY="$TRY_TOP/try"
 
-control=$(id -G)
-testing=$("$TRY" id -G 2>/dev/null)
+control=$(id -Gn)
+testing=$("$TRY" -D "$(mktemp -d)" -n id -Gn 2>/dev/null)
 
 if [ "$control" = "$testing" ]
 then
diff --git a/test/uidmapping.sh b/test/uidmapping.sh
index 395a4000..161dc6be 100755
--- a/test/uidmapping.sh
+++ b/test/uidmapping.sh
@@ -3,8 +3,8 @@
 TRY_TOP="${TRY_TOP:-$(git rev-parse --show-toplevel --show-superproject-working-tree)}"
 TRY="$TRY_TOP/try"
 
-control=$(id)
-testing=$(sudo "$TRY" -u "$USER" id)
+control=$(id -un)
+testing=$(sudo "$TRY" -D "$(mktemp -d)" -n -u "$USER" id -un)
 
 if [ "$control" = "$testing" ]
 then