diff --git a/dist-gpw.sh b/dist-gpw.sh
index f292e88..2420abb 100755
--- a/dist-gpw.sh
+++ b/dist-gpw.sh
@@ -3,13 +3,12 @@
 # Create a archive 'gpw32-*.zip' (gpwYMMDD.zip) with Win32 (MinGW) build
 # of the Golded+.
 
-if [ ! $OSTYPE = "cygwin" ]
+if [ ! "${TERM}" = "cygwin" ]
 then
   echo "This is not Cygwin enviroment, exit."
   exit
 fi
 
-
 date=`date +%Y%m%d`
 name=../gpw32-115-${date}.zip