

REF(1)                    Minix Programmer's Manual                     REF(1)


NAME
     ref - Display a C function header

SYNOPSIS
     ref [-t] [-c class]... [-f file]... tag

DESCRIPTION
     ref quickly locates and displays the header of a function.  To  do  this,
     ref  looks  in  the "tags" file for the line that describes the function,
     and then scans the source file for the function.   When  it  locates  the
     function,  it  displays  an  introductory  comment (if there is one), the
     function's declaration, and the declarations of all arguments.

SEARCH METHOD

     ref uses a fairly sophisticated tag look-up algorithm.  If you  supply  a
     filename  via  -f file, then elvis first scans the tags file for a static
     tag from that file.  This search is limited  to  the  tags  file  in  the
     current directory.

     If you supply a classname via -c class, then elvis  searches  for  a  tag
     from  that  class.   This search is not limited to the current directory;
     You can supply a list of directories in the environment variable TAGPATH,
     and  ref  will  search through the "tags" file in each directory until it
     finds a tag in the desired class.

     If that fails, ref will then try to look up an ordinary global tag.  This
     search checks all of the directories listed in TAGPATH, too.

     If you've given the -t flag, then ref will simply  output  the  tag  line
     that  it  found,  and then exit.  Without -t, though, ref will search for
     the tag line.  It will try to open the source file, which  should  be  in
     the same directory as the tags file where the tag was discovered.  If the
     source file doesn't exist, or is unreadable, then ref will try to open  a
     file called "refs" in that directory.  Either way, ref will try to locate
     the tag, and display whatever it finds.

INTERACTION WITH ELVIS

     ref is used by elvis' shift-K command.  If the cursor  is  located  on  a
     word  such  as  "splat",  in the file "foo.c", then elvis will invoke ref
     with the command "ref -f foo.c splat".

     If elvis has been compiled with the -DEXTERNAL_TAGS flag, then elvis will
     use  ref  to  scan  the tags files.  This is slower than the built-in tag
     searching, but it allows elvis  to  access  the  more  sophisticated  tag
     lookup  provided  by  ref.   Other  than  that,  external tags should act
     exactly like internal tags.




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REF(1)                    Minix Programmer's Manual                     REF(1)


OPTIONS

     -t   Output tag info, instead of the function header.

     -f file
          The tag might be a static function in file.  You can use several  -f
          flags to have ref consider static tags from more than one file.

     -c class
          The tag might be a member of class class.  You can  use  several  -c
          flags to have ref consider tags from more than one class.

FILES

     tags List of function names and their locations, generated by ctags.

     refs Function headers extracted from source files (optional).

ENVIRONMENT

     TAGPATH
          List of directories to be searched.  The elements in  the  list  are
          separated   by   either  semicolons  (for  MS-DOS,  Atari  TOS,  and
          AmigaDos), or by colons (every other operating  system).   For  each
          operating  system,  ref  has  a  built-in  default which is probably
          adequate.

NOTES

     You might want to generate a "tags" file the directory that contains  the
     source  code  for  standard  C  library  on  your  system.   If licensing
     restrictions prevent you from  making  the  library  source  readable  by
     everybody,  then  you  can  have  ctags  generate a "refs" file, and make
     "refs" readable by everybody.

     If your system doesn't come with the library source  code,  then  perhaps
     you can produce something workable from the lint libraries.

SEE ALSO
     elvis(1), ctags(1)

AUTHOR
     Steve Kirkendall
     kirkenda@cs.pdx.edu








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