filegroup Gets file group intfilegroup stringfilename Returns the group ID of the file, or &false; in case of an error. The group ID is returned in numerical format, use posix_getgrgid to resolve it to a group name. Upon failure, &false; is returned along with an error of level E_WARNING. ¬e.clearstatcache; &tip.fopen-wrapper.stat; See also fileowner, and safe_mode_gid.