This example can be used to separate the columns of a .csv file with a semicolon instead of a column. This is helpful if you want to change the default column separator when exporting from the front-end or from the Entries page on the back-end.

add_filter('frm_csv_column_sep', 'frm_csv_column_sep');
function frm_csv_column_sep($separator){
  return ';';
}