etags(1)                           GNU Tools                          etags(1)

       etags, ctags - generate tag file for Emacs, vi

       etags [-aCDGImRVh] [-i file] [-l language]
       [-o tagfile] [-r regexp]
       [--append] [--no-defines] [--no-globals] [--include=file]
       [--ignore-indentation] [--language=language] [--members]
       [--output=tagfile] [--regex=regexp] [--no-regex]
       [--ignore-case-regex=regexp] [--help] [--version] file ...

       ctags [-aCdgImRVh] [-BtTuvwx] [-l language]
       [-o tagfile] [-r regexp]
       [--append] [--backward-search] [--cxref] [--defines] [--forward-search]
       [--globals] [--ignore-indentation] [--language=language] [--members]
       [--output=tagfile] [--regex=regexp] [--ignore-case-regex=regexp]
       [--typedefs] [--typedefs-and-c++] [--update] [--no-warn] [--help]
       [--version] file ...

       The etags program is used to create a tag table file, in a format
       understood by emacs(1); the ctags program is used to create a similar
       table in a format understood by vi(1).  Both forms of the program
       understand the syntax of C, Objective C, C++, Java, Fortran, Ada,
       Cobol, Erlang, LaTeX, Emacs Lisp/Common Lisp, makefiles, Pascal, Perl,
       Postscript, Python, Prolog, Scheme and most assembler-like syntaxes.
       Both forms read the files specified on the command line, and write a
       tag table (defaults: TAGS for etags, tags for ctags) in the current
       working directory.  Files specified with relative file names will be
       recorded in the tag table with file names relative to the directory
       where the tag table resides.  Files specified with absolute file names
       will be recorded with absolute file names.  The programs recognize the
       language used in an input file based on its file name and contents.
       The --language switch can be used to force parsing of the file names
       following the switch according to the given language, overriding
       guesses based on filename extensions.

       Some options make sense only for the vi style tag files produced by
       ctags; etags does not recognize them.  The programs accept unambiguous
       abbreviations for long option names.

       -a, --append
              Append to existing tag file.  (For vi-format tag files, see also

       -B, --backward-search
              Tag files written in the format expected by vi contain regular
              expression search instructions; the -B option writes them using
              the delimiter `?', to search backwards through files.  The
              default is to use the delimiter `/', to search forwards through
              files.  Only ctags accepts this option.

              In C and derived languages, create tags for function
              declarations, and create tags for extern variables unless
              --no-globals is used.

       -d, --defines
              Create tag entries for C preprocessor constant definitions and
              enum constants, too.  This is the default behavior for etags.

       -D, --no-defines
              Do not create tag entries for C preprocessor constant
              definitions and enum constants.  This may make the tags file
              much smaller if many header files are tagged.  This is the
              default behavior for ctags.

       -g, --globals
              Create tag entries for global variables in C, C++, Objective C,
              Java, and Perl.  This is the default behavior for etags.

       -G, --no-globals
              Do not tag global variables.  Typically this reduces the file
              size by one fourth.  This is the default behavior for ctags.

       -i file, --include=file
              Include a note in the tag file indicating that, when searching
              for a tag, one should also consult the tags file file after
              checking the current file.  This options is only accepted by

       -I, --ignore-indentation
              Don't rely on indentation as much as we normally do.  Currently,
              this means not to assume that a closing brace in the first
              column is the final brace of a function or structure definition
              in C and C++.

       -l language, --language=language
              Parse the following files according to the given language.  More
              than one such options may be intermixed with filenames.  Use
              --help to get a list of the available languages and their
              default filename extensions.  The `auto' language can be used to
              restore automatic detection of language based on the file name.
              The `none' language may be used to disable language parsing
              altogether; only regexp matching is done in this case (see the
              --regex option).

       -m, --members
              Create tag entries for variables that are members of structure-
              like constructs in C++, Objective C, Java.

       -M, --no-members
              Do not tag member variables.  This is the default behavior.

              Only tag packages in Ada files.

       -o tagfile, --output=tagfile
              Explicit name of file for tag table; overrides default TAGS or
              tags.   (But ignored with -v or -x.)

       -r regexp, --regex=regexp

              Make tags based on regexp matching for each line of the files
              following this option, in addition to the tags made with the
              standard parsing based on language.  When using --regex, case is
              significant, while it is not with --ignore-case-regex. May be
              freely intermixed with filenames and the -R option.  The regexps
              are cumulative, i.e. each option will add to the previous ones.
              The regexps are of the form:

              where tagregexp is used to match the lines that must be tagged.
              It should not match useless characters.  If the match is such
              that more characters than needed are unavoidably matched by
              tagregexp, it may be useful to add a nameregexp, to narrow down
              the tag scope.  ctags ignores regexps without a nameregexp.  The
              syntax of regexps is the same as in emacs, augmented with
              intervals of the form \{m,n\}, as in ed or grep.
              Here are some examples.  All the regexps are quoted to protect
              them from shell interpretation.

              Tag the DEFVAR macros in the emacs source files:
              --regex='/[ \t]*DEFVAR_[A-Z_ \t(]+"\([^"]+\)"'

              Tag VHDL files (this example is a single long line, broken here
              for formatting reasons):
              --language=none --regex='/[ \t]*\(ARCHITECTURE\|\
              CONFIGURATION\) +[^ ]* +OF/' --regex='/[ \t]*\
              \|PROCEDURE\|PROCESS\|TYPE\)[ \t]+\([^ \t(]+\)/\3/'

              Tag TCL files (this last example shows the usage of a
              --lang=none --regex='/proc[ \t]+\([^ \t]+\)/\1/'

              A regexp can be preceded by {lang}, thus restricting it to match
              lines of files of the specified language.  Use etags --help to
              obtain a list of the recognised languages.  This feature is
              particularly useful inside regex files.  A regex file contains
              one regex per line.  Empty lines, and those lines beginning with
              space or tab are ignored.  Lines beginning with @ are references
              to regex files whose name follows the @ sign.  Other lines are
              considered regular expressions like those following --regex.
              For example, the command
              etags --regex=@regex.file *.c
              reads the regexes contained in the file regex.file.

       -R, --no-regex
              Don't do any more regexp matching on the following files.  May
              be freely intermixed with filenames and the --regex option.

       -t, --typedefs
              Record typedefs in C code as tags.  Since this is the default
              behaviour of etags, only ctags accepts this option.

       -T, --typedefs-and-c++
              Generate tag entries for typedefs, struct, enum, and union tags,
              and C++ member functions.  Since this is the default behaviour
              of etags, only ctags accepts this option.

       -u, --update
              Update tag entries for files specified on command line, leaving
              tag entries for other files in place.  Currently, this is
              implemented by deleting the existing entries for the given files
              and then rewriting the new entries at the end of the tags file.
              It is often faster to simply rebuild the entire tag file than to
              use this.  Only ctags accepts this option.

       -v, --vgrind
              Instead of generating a tag file, write index (in vgrind format)
              to standard output.  Only ctags accepts this option.

       -w, --no-warn
              Suppress warning messages about duplicate entries.  The etags
              program does not check for duplicate entries, so this option is
              not allowed with it.

       -x, --cxref
              Instead of generating a tag file, write a cross reference (in
              cxref format) to standard output.  Only ctags accepts this

       -h, -H, --help
              Print usage information.

       -V, --version
              Print the current version of the program (same as the version of
              the emacs etags is shipped with).

       `emacs' entry in info; GNU Emacs Manual, Richard Stallman.
       cxref(1), emacs(1), vgrind(1), vi(1).

       Copyright (c) 1999, 2001 Free Software Foundation, Inc.

       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.1 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and no Back-Cover Texts.

       This document is part of a collection distributed under the GNU Free
       Documentation License.  If you want to distribute this document
       separately from the collection, you can do so by adding a copy of the
       license to the document, as described in section 6 of the license.  A
       copy of the license is included in the gfdl(1) man page, and in the
       section entitled "GNU Free Documentation License" in the Emacs manual.

GNU Tools                          08apr2001                          etags(1)