ctags(1)

ctags -- create a tags file for use with vi

Synopsis

ctags [-aBFtuvwx] [-f tagsfile] file ...

Description

ctags makes a tags file for ex(1) from the specified C, Pascal, FORTRAN, YACC, and LEX sources. A tags file gives the locations of specified objects (in this case functions and typedefs) in a group of files. Each line of the tags file contains the object name, the file in which it is defined, and an address specification for the object definition. Functions are searched with a pattern, typedefs with a line number. Specifiers are given in separate fields on the line, separated by <Space> or <Tab> characters. Using the tags file, ex can quickly find these objects definitions.

Normally ctags places the tag descriptions in a file called tags; this may be overridden with the -f option.

Files with names ending in .c or .h are assumed to be C source files and are searched for C routine and macro definitions. Files with names ending in .y are assumed to be YACC source files. Files with names ending in .l are assumed to be LEX files. Others are first examined to see if they contain any Pascal or FORTRAN routine definitions; if not, they are processed again looking for C definitions.

The tag main is treated specially in C programs. The tag formed is created by prepending M to file, with a trailing .c removed, if any, and leading pathname components also removed. This makes use of ctags practical in directories with more than one program.

The following options are available:

-a: Append output to an existing tags file.
-B: Use backward searching patterns (? . . . ?).
-F: Use forward searching patterns (/ . . . /) (default).
-t: Create tags for typedefs.
-u: Update the specified files in tags, 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 usually faster to simply rebuild the tags file.
-v: Produce on the standard output an index listing the function name, file name, and page number (assuming 64 line pages). Since the output will be sorted into lexicographic order, it may be desired to run the output through sort -f.
-w: Suppress warning diagnostics.
-x: Produce 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.

Files

tags: output tags file

References

ex(1), vi(1)

Notices

Recognition of functions, subroutines and procedures for FORTRAN and Pascal is done in a very simple-minded 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.

The method of deciding whether to look for C or Pascal and FORTRAN functions is a hack.

ctags does not know about #ifdefs.

ctags should know about Pascal types. Relies on the input being well formed to detect typedefs. Use of -tx shows only the last line of typedefs.