cscope - interactively examine a C program


   cscope    [-bCcdehkLlqRTUuVvX]   [-Fsymfile]   [-freffile]   [-Iincdir]
   [-inamefile] [-0123456789pattern] [-pn] [-sdir] [files]


   cscope is an interactive, screen-oriented tool that allows the user  to
   browse through C source files for specified elements of code.

   By  default, cscope examines the C (.c and .h), lex (.l), and yacc (.y)
   source files in the current directory.  cscope may also be invoked  for
   source files named on the command line. In either case, cscope searches
   the standard directories for #include files that it does  not  find  in
   the  current  directory.   cscope uses a symbol cross-reference, called
   cscope.out by default, to locate  functions,  function  calls,  macros,
   variables, and preprocessor symbols in the files.

   cscope  builds  the symbol cross-reference the first time it is used on
   the source files  for  the  program  being  browsed.  On  a  subsequent
   invocation,  cscope  rebuilds the cross-reference only if a source file
   has changed or the list of source files is different. When  the  cross-
   reference  is rebuilt, the data for the unchanged files are copied from
   the old cross-reference, which makes rebuilding faster than the initial


   Some  command line arguments can only occur as the only argument in the
   execution of cscope.  They cause the program to  just  print  out  some
   output and exit immediately:

   -h     View the long usage help display.

   -V     Print on the first line of screen the version number of cscope.

   --help Same as -h

          Same as -V

   The following options can appear in any combination:

   -b     Build the cross-reference only.

   -C     Ignore letter case when searching.

   -c     Use  only ASCII characters in the cross-reference file, that is,
          do not compress the data.

   -d     Do not update the cross-reference.

   -e     Suppress the <Ctrl>-e command prompt between files.

          Read symbol reference lines from symfile.  (A  symbol  reference
          file  is  created  by > and >>, and can also be read using the <
          command,  described  under  ``Issuing   Subsequent   Requests'',

          Use  reffile  as  the  cross-reference  file name instead of the
          default "cscope.out".

          Look in incdir (before looking in $INCDIR,  the  standard  place
          for  header files, normally /usr/include) for any #include files
          whose names do not begin with ``/'' and that are  not  specified
          on  the  command  line or in namefile below. (The #include files
          may be specified with either double quotes or  angle  brackets.)
          The  incdir  directory  is  searched  in addition to the current
          directory (which is searched first) and the standard list (which
          is  searched  last).  If more than one occurrence of -I appears,
          the directories are searched in the order  they  appear  on  the
          command line.

          Browse  through  all  source  files  whose  names  are listed in
          namefile (file names separated by spaces,  tabs,  or  new-lines)
          instead   of  the  default  name  list  file,  which  is  called
          cscope.files. If this option is specified,  cscope  ignores  any
          file  names appearing on the command line. The argument namefile
          can be set to ``-'' to accept a list of files from the  standard
          input.   Filenames  in the namefile that contain whitespace have
          to  be  enclosed  in  "double  quotes".   Inside   such   quoted
          filenames,  any double-quote and backslash characters have to be
          escaped by backslashes.

   -k     ``Kernel Mode'', turns off the use of the  default  include  dir
          (usually  /usr/include) when building the database, since kernel
          source trees generally do not use it.

   -L     Do a single search with line-oriented output when used with  the
          -num pattern option.

   -l     Line-oriented interface (see ``Line-Oriented Interface'' below).

          Go to input field num (counting from 0) and find pattern.

   -Ppath Prepend  path  to  relative  file  names  in  a pre-built cross-
          reference file so you do not have to  change  to  the  directory
          where  the  cross-reference  file was built. This option is only
          valid with the -d option.

   -pn    Display the last n file path components instead of  the  default
          (1). Use 0 not to display the file name at all.

   -q     Enable  fast  symbol  lookup  via an inverted index. This option
          causes  cscope  to  create   2   more   files   (default   names
          ``''  and  ``cscope.po.out'')  in  addition  to the
          normal database. This allows a faster  symbol  search  algorithm
          that  provides  noticeably  faster  lookup performance for large

   -R     Recurse subdirectories during search for source files.

   -sdir  Look in dir for additional source files. This option is  ignored
          if source files are given on the command line.

   -T     Use  only the first eight characters to match against C symbols.
          A regular expression containing special characters other than  a
          period  (.)  will  not match any symbol if its minimum length is
          greater than eight characters.

   -U     Check file time stamps. This option will update the  time  stamp
          on the database even if no files have changed.

   -u     Unconditionally  build the cross-reference file (assume that all
          files have changed).

   -v     Be more verbose in line-oriented mode.  Output progress  updates
          during database building and searches.

   -X     Remove  the  cscope  reference  file  and  inverted indexes when

   files  A list of file names to operate on.

   The -I, -c, -k, -p, -q, and -T options can also be in the  cscope.files

   Requesting the initial search
   After the cross-reference is ready, cscope will display this menu:

   Find this C symbol:
   Find this function definition:
   Find functions called by this function:
   Find functions calling this function:
   Find this text string:
   Change this text string:
   Find this egrep pattern:
   Find this file:
   Find files #including this file:
   Find assignments to this symbol:

   Press  the  <Up> or <Down> keys repeatedly to move to the desired input
   field, type the text to search for, and then press the <Return> key.

   Issuing subsequent requests
   If the search is successful, any of these single-character commands can
   be used:

          Edit the file referenced by the given line number.

          Display next set of matching lines.

   <Tab>  Alternate between the menu and the list of matching lines

   <Up>   Move to the previous menu item (if the cursor is in the menu) or
          move to the previous matching line (if  the  cursor  is  in  the
          matching line list.)

   <Down> Move  to  the  next  menu item (if the cursor is in the menu) or
          move to the next matching line (if the cursor is in the matching
          line list.)

   +      Display next set of matching lines.

   -      Display previous set of matching lines.

   ^e     Edit displayed files in order.

   >      Write the displayed list of lines to a file.

   >>     Append the displayed list of lines to a file.

   <      Read  lines  from  a  file  that  is  in symbol reference format
          (created by > or >>), just like the -F option.

   ^      Filter all  lines  through  a  shell  command  and  display  the
          resulting lines, replacing the lines that were already there.

   |      Pipe  all  lines  to  a  shell  command and display them without
          changing them.

   At any time these single-character commands can also be used:

          Move to next input field.

   ^n     Move to next input field.

   ^p     Move to previous input field.

   ^y     Search with the last text typed.

   ^b     Move to previous input field and search pattern.

   ^f     Move to next input field and search pattern.

   ^c     Toggle ignore/use letter case  when  searching.  (When  ignoring
          letter  case,  search  for  ``FILE''  will  match  ``File''  and

   ^r     Rebuild the cross-reference.

   !      Start an interactive shell (type ^d to return to cscope).

   ^l     Redraw the screen.

   ?      Give help information about cscope commands.

   ^d     Exit cscope.

   NOTE: If the first character of the text to be searched for matches one
   of the above commands, escape it by typing a (backslash) first.

   Substituting new text for old text

   After the text to be changed has been typed, cscope will prompt for the
   new text, and then it will display the lines containing the  old  text.
   Select the lines to be changed with these single-character commands:

          Mark or unmark the line to be changed.

   *      Mark or unmark all displayed lines to be changed.

          Display next set of lines.

   +      Display next set of lines.

   -      Display previous set of lines.

   a      Mark or unmark all lines to be changed.

   ^d     Change the marked lines and exit.

   <Esc>  Exit without changing the marked lines.

   !      Start an interactive shell (type ^d to return to cscope).

   ^l     Redraw the screen.

   ?      Give help information about cscope commands.

   Special keys
          If  your  terminal  has  arrow keys that work in vi, you can use
          them to move around the input fields. The up-arrow key is useful
          to  move  to the previous input field instead of using the <Tab>
          key repeatedly. If you have <CLEAR>, <NEXT>, or <PREV> keys they
          will act as the ^l, +, and - commands, respectively.

   Line-Oriented interface
   The  -l  option  lets  you use cscope where a screen-oriented interface
   would not be useful, for example, from another screen-oriented program.

   cscope will prompt with >> when it is ready for an input line  starting
   with  the  field  number  (counting from 0) immediately followed by the
   search pattern, for example, ``lmain'' finds the definition of the main

   If  you  just want a single search, instead of the -l option use the -L
   and -num pattern options, and you won't get the >> prompt.

   For -l, cscope outputs the number of reference lines cscope: 2 lines

   For each reference found, cscope outputs a line consisting of the  file
   name,  function  name, line number, and line text, separated by spaces,
   for example, main.c main 161 main(argc, argv)

   Note that the editor is not  called  to  display  a  single  reference,
   unlike the screen-oriented interface.

   You  can  use  the  c  command  to  toggle  ignore/use letter case when
   searching. (When ignoring letter case, search for ``FILE''  will  match
   ``File'' and ``file''.)

   You can use the r command to rebuild the database.

   cscope  will  quit  when  it  detects  end-of-file,  or  when the first
   character of an input line is ``^d'' or ``q''.


          Overrides the EDITOR and VIEWER variables. Use this if you  wish
          to  use  a  different  editor with cscope than that specified by
          your EDITOR/VIEWER variables.

          Format of the line number flag  for  your  editor.  By  default,
          cscope  invokes  your  editor  via the equivalent of ``editor +N
          file'', where ``N'' is the line number that  the  editor  should
          jump  to.  This  format  is  used  by both emacs and vi. If your
          editor needs something different, specify it in  this  variable,
          with  ``%s''  as a placeholder for the line number.  Ex: if your
          editor needs to be invoked as ``editor -#103  file''  to  go  to
          line 103, set this variable to ``-#%s''.

          Set  this variable to ``yes'' if your editor needs to be invoked
          with the line number option after the filename to be edited.  To
          continue the example from CSCOPE_LINEFLAG, above: if your editor
          needs to see ``editor  file  -#number'',  set  this  environment
          variable. Users of most standard editors (vi, emacs) do not need
          to set this variable.

   EDITOR Preferred editor, which defaults to vi.

   HOME   Home directory, which is automatically set at login.

          Colon-separated list  of  directories  to  search  for  #include

   SHELL  Preferred shell, which defaults to sh.

          Colon-separated  list  of  directories  to search for additional
          source files.

   TERM   Terminal type, which must be a screen terminal.

          Terminal information directory full path name. If your  terminal
          is  not  in  the  standard  terminfo  directory,  see curses and
          terminfo for how to make your own terminal description.

   TMPDIR Temporary file directory, which defaults to /var/tmp.

   VIEWER Preferred file display program (such as less),  which  overrides
          EDITOR (see above).

   VPATH  A  colon-separated  list  of  directories, each of which has the
          same directory structure below  it.  If  VPATH  is  set,  cscope
          searches for source files in the directories specified; if it is
          not set, cscope searches only in the current directory.


          Default files containing -I, -p, -q, and -T options and the list
          of source files (overridden by the -i option).

          Symbol cross-reference file (overridden by the -f option), which
          is put in the home directory if it  cannot  be  created  in  the
          current directory.
          Default  files  containing  the  inverted  index  used for quick
          symbol searching (-q option). If you use the -f option to rename
          the cross-reference file (so it's not cscope.out), the names for
          these inverted index files will be created by adding
           .in and .po to the name you supply with -f. For example, if you
          indicated  -f  xyz,  then  these files would be named and

   INCDIR Standard directory for #include files (usually /usr/include).


   cscope recognizes function definitions of the form:
   fname blank ( args ) white arg_decs white {

   where: fname is the function name

   blank  is zero or more spaces, tabs,  vtabs,  form  feeds  or  carriage
          returns, not including newlines

   args   is any string that does not contain a ``"'' or a newline

   white  is  zero  or  more  spaces,  tabs,  vtabs,  form feeds, carriage
          returns or newlines

          are zero or more argument  declarations  (arg_decs  may  include
          comments and white space)

   It  is  not  necessary  for  a  function  declaration  to  start at the
   beginning of a line. The return type may  precede  the  function  name;
   cscope  will still recognize the declaration. Function definitions that
   deviate from this form will not be recognized by cscope.

   The ``Function'' column of the search output for the menu  option  Find
   functions  called  by  this function: input field will only display the
   first function called in the line, that is, for this function

            return (f() + g());

   the display would be

      Functions called by this function: e
      File Function Line
      a.c f 3 return(f() + g());

   Occasionally, a function definition  or  call  may  not  be  recognized
   because  of  braces  inside  #if  statements.  Similarly,  the use of a
   variable may be incorrectly recognized as a definition.

   A typedef name preceding a preprocessor statement will  be  incorrectly
   recognized as a global definition, for example,

    LDFILE  *
    #if AR16WR

   Preprocessor  statements  can  also prevent the recognition of a global
   definition, for example,

    char flag
         = -1

   A function declaration inside a function is incorrectly recognized as a
   function call, for example,

            void g();

   is incorrectly recognized as a call to g.

   cscope  recognizes  C++  classes  by looking for the class keyword, but
   doesn't recognize that  a  struct  is  also  a  class,  so  it  doesn't
   recognize  inline  member  function definitions in a structure. It also
   doesn't expect the class keyword in  a  typedef  ,  so  it  incorrectly
   recognizes X as a definition in

    typedef class X  *  Y;

   It also doesn't recognize operator function definitions

    Bool Feature::operator==(const Feature & other)

   Nor  does  it  recognize  function  definitions with a function pointer

    ParseTable::Recognize(int startState, char *pattern,
      int finishState, void (*FinalAction)(char *))


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