Check std_data_ln already created

Add / to std_data in ln command


mysql-test/mysql-test-run.sh:
  Check if std_data_ln is already created
  Add / to std_data to create a symlink to a dir an not a file.

mysql-test/mysql-test-run.sh

@@ -608,8 +608,10 @@ fi
 [ -d $MYSQL_TEST_DIR/var/tmp ] || mkdir $MYSQL_TEST_DIR/var/tmp
 [ -d $MYSQL_TEST_DIR/var/run ] || mkdir $MYSQL_TEST_DIR/var/run
 [ -d $MYSQL_TEST_DIR/var/log ] || mkdir $MYSQL_TEST_DIR/var/log
-ln -s $MYSQL_TEST_DIR/std_data $MYSQL_TEST_DIR/var/std_data_ln
- 
+if ! test -L $MYSQL_TEST_DIR/var/std_data_ln ; then
+  ln -s $MYSQL_TEST_DIR/std_data/ $MYSQL_TEST_DIR/var/std_data_ln
+fi
+
 if test ${COLUMNS:-0} -lt 80 ; then COLUMNS=80 ; fi
 E=`$EXPR $COLUMNS - 8`
 DASH72=`$ECHO '-------------------------------------------------------'|$CUT -c 1-$E`