Use tr instead of bash specific command

diff --git a/deal.II-toolchain/packages/dealii-prepare.package b/deal.II-toolchain/packages/dealii-prepare.package
index 025573f6821b68782e59aa6b710d55a76f7d36ad..8f5b845005bd2c86c50f3d9648039835f197b05d 100644 (file)
--- a/deal.II-toolchain/packages/dealii-prepare.package
+++ b/deal.II-toolchain/packages/dealii-prepare.package
@@ -16,7 +16,7 @@ unset option
 unset PACKAGE_NAME
 
 # Transform upper case to lower case.
-PACKAGES_OFF=${PACKAGES_OFF,,}
+PACKAGES_OFF=`echo "$PACKAGES_OFF" | tr '[:upper:]' '[:lower:]'`
 
 if [ ! -z "${PACKAGES_OFF}" ]; then
     cecho ${WARN} "deal.II: forcing package skip for: ${PACKAGES_OFF}"