Re: learning dragonfly or C...

[Max Okumoto <okumoto@home>]

George Georgalis wrote:
[stuff deleted]
> When jumping into a block of code that has functions and
> declarations, what is an efficient way to to find those definition
> amidst all the includes, paths and Makefiles of the whole tree,
> without completely losing your place? (eg I'd like to reference
> O_RDONLY and fp_close)
[stuff deleted]

If you use vi as your editor you can navigate code using a
tags file, other editors have similar functionality (for
example emacs uses etags).

% man 1 vi
. ..
   -t     Start editing at the specified tag.  (See ctags(1)).
. ..
. ..
   <control-]>
        Push a tag reference onto the tag stack.  In  gtagsmode, if  at
        the  first  column of line, locate function references otherwise
        function definitions.

   <control-^>
        Switch to the most recently edited file.
. ..

The following command will open the file containing the function
definition for JobCondPassSig.

	% vi -t JobCondPassSig

Or when the cursor is on the first character of a function name,
type <ctrl-]>, this should causes the editor to open the file
containing the definition of the function. Typing <ctrl-6> will
return you to the previous file and location.

The tags file is created by running ctags on your source files.
There is also a target in Makefiles that includes 'bsd.prog.mk'
or 'bsd.lib.mk' called ctags.

	% cd /usr/src/usr.bin/make
	% setenv CTAGS ctags
	% make tags
	Duplicate entry in file job.c, line 243: MESSAGE
	Second entry ignored
	Duplicate entry in file job.c, line 262: KILL
	Second entry ignored
	Duplicate entry in file job.c, line 264: KILL
	Second entry ignored
	Duplicate entry in file targ.c, line 493: PRINTBIT
	Second entry ignored
	Duplicate entry in file targ.c, line 494: PRINTDBIT
	Second entry ignored

	takai.home-2924% vi -t JobCondPassSig

If you are interested in the kernel source then there is a
target in /usr/src/sys/i386/Makefile which will create a tags
file for the whole kernel.

				Max