Filenames for the tag command, separated by spaces or commas. To include a space or comma in a file name, precede it with a backslash (see option-backslash about including spaces and backslashes). When a file name starts with "./", the '.' is replaced with the path of the current file. But only when the 'd' flag is not included in 'cpoptions'. Environment variables are expanded :set_env. Also see tags-option. "*", "" and other wildcards can be used to search for tags files in a directory tree. See file-searching. E.g., "/lib/ /tags" will find all files named "tags" below "/lib". The filename itself cannot contain wildcards, it is used as-is. E.g., "/lib/** /tags?" will find files called "tags?". The tagfiles() function can be used to get a list of the file names actually used. If Vim was compiled with the +emacs_tags feature, Emacs-style tag files are also supported. They are automatically recognized. The default value becomes "./tags,./TAGS,tags,TAGS", unless case differences are ignored (MS-Windows). emacs-tags The use of :set+= and :set-= is preferred when adding or removing file names from the list. This avoids problems when a future version uses another default.

(default "./tags,tags", when compiled with +emacs_tags: "./tags,./TAGS,tags,TAGS")