diff --git a/setup-bioc/get-r-version.sh b/setup-bioc/get-r-version.sh
index 887b1ce..6b6696b 100755
--- a/setup-bioc/get-r-version.sh
+++ b/setup-bioc/get-r-version.sh
@@ -8,7 +8,7 @@
 #   selection <- tolower( input_arguments[3] )
 # }
 
-mapping_file=`realpath $1`
+mapping_file=`readlink -f $1`
 bioc_version=`echo $2 | tr '[:upper:]' '[:lower:]'`
 selection=`echo $3 | tr '[:upper:]' '[:lower:]'`