etags(1) | GNU Tools | etags(1) |
etags, ctags - generate tag file for Emacs, vi
etags [-aCDGIQRVh] [-i file] [-l language]
[-o tagfile] [-r regexp] [--parse-stdin=file]
[--append] [--no-defines] [--globals] [--no-globals] [--no-line-directive]
[--include=file] [--ignore-indentation] [--language=language]
[--members] [--no-members] [--output=tagfile] [--class-qualify]
[--regex=regexp] [--no-regex] [--help] [--version] file
...
ctags [-aCdgIQRVh] [-BtTuvwx] [-l language]
[-o tagfile] [-r regexp] [--parse-stdin=file]
[--append] [--backward-search] [--cxref] [--no-defines] [--globals]
[--no-globals] [--no-line-directive] [--ignore-indentation]
[--language=language] [--members] [--no-members] [--class-qualify]
[--output=tagfile] [--regex=regexp] [--update] [--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, Forth, Go, HTML, LaTeX, Emacs Lisp/Common Lisp, Lua, Makefile, Pascal, Perl, Ruby, PHP, 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. If the tag table is in /dev or is the standard output, however, the file names are made relative to the working directory. Files specified with absolute file names will be recorded with absolute file names. Files generated from a source file--like a C file generated from a source Cweb file--will be recorded with the name of the source file. Compressed files are supported using gzip, bzip2, and xz. 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.
Make tags based on regexp matching for the files following
this option, in addition to the tags made with the standard parsing
based on language. May be freely intermixed with filenames and the
-R option. The regexps are cumulative, i.e., each such option
will add to the previous ones. The regexps are of one of the forms:
[{language}]/tagregexp/[nameregexp/]modifiers
@regexfile
where tagregexp is used to match the tag. 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. The following character escape sequences are
supported: \a, \b, \d, \e, \f, \n, \r, \t, \v, which respectively stand
for the ASCII characters BEL, BS, DEL, ESC, FF, NL, CR, TAB, VT.
The modifiers are a sequence of 0 or more characters among
i, which means to ignore case when matching; m, which
means that the tagregexp will be matched against the whole file
contents at once, rather than line by line, and the matching sequence
can match multiple lines; and s, which implies m and means
that the dot character in tagregexp matches the newline char as
well.
The separator, which is / in the examples, can be any character
different from space, tab, braces and @. If the separator
character is needed inside the regular expression, it must be quoted by
preceding it with \.
The optional {language} prefix means that the tag
should be created only for files of language language, and
ignored otherwise. This is particularly useful when storing many
predefined regexps in a file.
In its second form, regexfile is the name of a file that contains a
number of arguments to the --regex= option, one per line. Lines
beginning with a space or tab are assumed to be comments, and
ignored.
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]*\
\(ATTRIBUTE\|ENTITY\|FUNCTION\|PACKAGE\( BODY\)?\
\|PROCEDURE\|PROCESS\|TYPE\)[ \t]+\([^ \t(]+\)/\3/'
Tag TCL files (this last example shows the usage of a
tagregexp):
--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 recognized 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.
"emacs" entry in info; GNU Emacs
Manual, Richard Stallman.
cxref(1), emacs(1), vgrind(1),
vi(1).
Copyright 1992, 1999, 2001-2018 Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies of this document provided the copyright notice and this permission notice are preserved on all copies.
Permission is granted to copy and distribute modified versions of this document under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one.
Permission is granted to copy and distribute translations of this document into another language, under the above conditions for modified versions, except that this permission notice may be stated in a translation approved by the Free Software Foundation.
23nov2001 | GNU Tools |