4.3BSD-Tahoe/usr/man/cat1/ctags.0

CTAGS(1)	    UNIX Programmer's Manual		 CTAGS(1)



NNAAMMEE
     ctags - create a tags file

SSYYNNOOPPSSIISS
     ccttaaggss [ --BBFFaaddttuuwwvvxx ] [ --ff _t_a_g_s_f_i_l_e ] name ...

DDEESSCCRRIIPPTTIIOONN
     _C_t_a_g_s makes a tags file for _e_x(1) from the specified C, Pas-
     cal, Fortran, YACC, lex, and lisp sources.  A tags file
     gives the locations of specified objects in a group of
     files.  Each line of the tags file contains the object name,
     the file in which it is defined, and a search pattern for
     the object definition, separated by white-space.  Using the
     _t_a_g_s file, _e_x(1) can quickly locate these object defini-
     tions.  Depending on the options provided to _c_t_a_g_s, objects
     will consist of subroutines, typedefs, defines, structs,
     enums and unions.

     Yacc and lex files each have a special tag.  _Y_y_p_a_r_s_e is the
     start of the second section of the yacc file, and _y_y_l_e_x is
     the start of the second section of the lex file.

     If the --xx flag is given, _c_t_a_g_s produces a list of object
     names, the line number and file name on which each is
     defined, as well as the text of that line and prints this on
     the standard output.  This is a simple index which can be
     printed out as an off-line readable function index.

     If the --vv flag is given, an index of the form expected by
     _v_g_r_i_n_d(1) is produced on the standard output.  This listing
     contains the object name, file name, and page number (assum-
     ing 64 line pages).  Since the output will be sorted into
     lexicographic order, it may be desired to run the output
     through ssoorrtt --ff.  Sample use:
	  ctags -v files | sort -f > index
	  vgrind -x index

     Normally _c_t_a_g_s places the tag descriptions in a file called
     _t_a_g_s; this may be overridden with the --ff option.

     Files whose names end in ..cc or ..hh are assumed to be C source
     files and are searched for C style routine and macro defini-
     tions.  Files whose names end in ..yy are assumed to be YACC
     source files.  Files whose names end in ..ll are assumed to be
     lisp files if their first non-blank character is `;', `(',
     or `[', otherwise, they are treated as lex files.	Other
     files are first examined to see if they contain any Pascal
     or Fortran routine definitions, and, if not, are searched
     for C style definitions.

     Other options are:




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CTAGS(1)	    UNIX Programmer's Manual		 CTAGS(1)



     --FF   use forward searching patterns (/.../) (the default).

     --BB   use backward searching patterns (?...?).

     --aa   append to _t_a_g_s file.

     --dd   create tags for #_d_e_f_i_n_e_s that don't take arguments;
	  #_d_e_f_i_n_e_s that take arguments are tagged automatically.

     --tt   create tags for typedefs, structs, unions, and enums.

     --ww   suppress warning diagnostics.

     --uu   update the specified files in the _t_a_g_s file, that is,
	  all references to them are deleted, and the new values
	  are appended to the file.  (Beware: this option is
	  implemented in a way which is rather slow; it is usu-
	  ally faster to simply rebuild the _t_a_g_s file.)

     The tag _m_a_i_n is treated specially in C programs.  The tag
     formed is created by prepending _M to the name of the file,
     with the trailing ..cc and any leading pathname components
     removed.  This makes use of _c_t_a_g_s practical in directories
     with more than one program.

FFIILLEESS
     tags      default output tags file

DDIIAAGGNNOOSSTTIICCSS
     _C_t_a_g_s exits with a value of 1 if an error occurred, where
     duplicate objects are not considered errors, 0 otherwise.

SSEEEE AALLSSOO
     ex(1), vi(1)

AAUUTTHHOORR
     Ken Arnold; FORTRAN added by Jim Kleckner; Bill Joy added
     Pascal and --xx, replacing _c_x_r_e_f; C typedefs added by Ed
     Pelegri-Llopart.

BBUUGGSS
     Recognition of ffuunnccttiioonnss, ssuubbrroouuttiinneess and pprroocceedduurreess for
     FORTRAN and Pascal is done is a very simpleminded way.  No
     attempt is made to deal with block structure; if you have
     two Pascal procedures in different blocks with the same name
     you lose.	_C_t_a_g_s doesn't understand about Pascal types.

     The method of deciding whether to look for C, Pascal or FOR-
     TRAN functions is a hack.

     _C_t_a_g_s relies on the input being well formed, and any syntac-
     tical errors will completely confuse it.  It also finds some



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CTAGS(1)	    UNIX Programmer's Manual		 CTAGS(1)



     legal syntax confusing; for example, as it doesn't under-
     stand #_i_f_d_e_f's, (incidentally, that's a feature, not a bug)
     any code with unbalanced braces inside #_i_f_d_e_f's will cause
     it to become somewhat disoriented.  In a similar fashion,
     multiple line changes within a definition will cause it to
     enter the last line of the object, rather than the first, as
     the searching pattern.  The last line of multiple line
     _t_y_p_e_d_e_f's will similarly be noted.















































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