{not available when compiled without the |+quickfix| feature} Name of the errorfile for the QuickFix mode (see |:cf|). When the "-q" command-line argument is used, 'errorfile' is set to the following argument. See |-q|. NOT used for the ":make" command. See 'makeef' for that. Environment variables are expanded |:set_env|. See |option-backslash| about including spaces and backslashes. This option cannot be set from a |modeline| or in the |sandbox|, for security reasons.