           ncurses - CRT screen handling and optimization package

## SYNOPSIS

           #include <curses.h>

## DESCRIPTION

           The curses library routines give the user a terminal-inde-
           pendent method of updating character screens with  reason-
           able  optimization.  This implementation is ``new curses''
           (ncurses) and is the approved replacement for 4.4BSD clas-
           sic curses, which has been discontinued.

           The  ncurses  routines  emulate  the curses(3X) library of
           System V Release 4 UNIX, and the XPG4 curses standard (XSI
           curses)  but the ncurses library is freely redistributable
           in source form.  Differences from the SVr4 curses are sum-
           marized  under  the EXTENSIONS and BUGS sections below and
           described in detail in the EXTENSIONS and BUGS sections of
           individual man pages.

           A  program  using  these  routines must be linked with the
           -lncurses option, or (if it has been generated)  with  the
           debugging  library  -lncurses_g.   (Your system integrator
           may also have installed these libraries  under  the  names
           -lcurses and -lcurses_g.)  The ncurses_g library generates
           trace logs (in a file called 'trace' in the current direc-
           tory) that describe curses actions.

           The  ncurses  package supports: overall screen, window and
           pad manipulation; output to windows and pads; reading ter-
           minal  input;  control  over terminal and curses input and
           output options; environment query routines; color  manipu-
           lation; use of soft label keys; terminfo capabilities; and
           access to low-level terminal-manipulation routines.

           To initialize the routines, the routine initscr or newterm
           must  be called before any of the other routines that deal
           with windows and screens are  used.   The  routine  endwin
           must be called before exiting.  To get character-at-a-time
           input without echoing (most interactive,  screen  oriented
           programs  want  this),  the  following  sequence should be
           used:

                 initscr(); cbreak(); noecho();

           Most programs would additionally use the sequence:

                 nonl();
                 intrflush(stdscr, FALSE);
                 keypad(stdscr, TRUE);

           Before a curses program is run, the tab stops of the  ter-
           the tput init command after the shell environment variable
           TERM has been exported.  tset(1)  is  usually  responsible
           for doing this.  [See terminfo(5) for further details.]

           The  curses  library  permits  manipulation of data struc-
           tures, called windows, which can be  thought  of  as  two-
           dimensional  arrays of characters representing all or part
           of a CRT screen.  A default window called stdscr, which is
           the  size of the terminal screen, is supplied.  Others may
           be created with newwin.

           Note that curses  does  not  handle  overlapping  windows,
           that's  done by the panel(3X) library. This means that you
           can either use stdscr or divide the screen into tiled win-
           dows  and  not  using  stdscr  at all. Mixing the two will
           result in unpredictable, and undesired, effects.

           Windows are referred to by variables declared as WINDOW *.
           These   data  structures  are  manipulated  with  routines
           described here and elsewhere in the ncurses manual  pages.
           Among  which  the  most basic routines are move and addch.
           More general versions of these routines are included  with
           names  beginning  with  w,  allowing the user to specify a
           window.  The routines not beginning with w affect stdscr.)

           After  using  routines  to manipulate a window, refresh is
           called, telling curses to make the user's CRT screen  look
           like  stdscr.   The characters in a window are actually of
           type chtype, (character and attribute data) so that  other
           information  about  the  character may also be stored with
           each character.

           Special windows  called  pads  may  also  be  manipulated.
           These are windows which are not constrained to the size of
           the screen and whose contents need not be completely  dis-
           played.  See curs_pad(3X) for more information.

           In  addition  to  drawing  characters on the screen, video
           attributes and colors may be supported, causing the  char-
           acters  to show up in such modes as underlined, in reverse
           video, or in color on terminals that support such  display
           enhancements.  Line drawing characters may be specified to
           be output.  On input, curses is  also  able  to  translate
           arrow  and  function  keys  that transmit escape sequences
           into single values.  The video  attributes,  line  drawing
           characters,   and  input  values  use  names,  defined  in
           <curses.h>, such as A_REVERSE, ACS_HLINE, and KEY_LEFT.

           If the environment variables LINES and COLUMNS are set, or
           if  the program is executing in a window environment, line
           and column information in the  environment  will  override
           information read by terminfo.  This would effect a program

           If  the environment variable TERMINFO is defined, any pro-
           gram using curses checks for a local  terminal  definition
           before  checking  in  the standard place.  For example, if
           TERM is set to att4424, then the compiled terminal defini-
           tion is found in

                 @DATADIR@/terminfo/a/att4424.

           (The a is copied from the first letter of att4424 to avoid
           creation of huge directories.)  However,  if  TERMINFO  is
           set to $HOME/myterms, curses first checks

                 $HOME/myterms/a/att4424,

           and if that fails, it then checks

                 @DATADIR@/terminfo/a/att4424.

           This  is useful for developing experimental definitions or
           when write permission in @DATADIR@/terminfo is not  avail-
           able.

           The  integer  variables  LINES  and  COLS  are  defined in
           <curses.h> and will be filled in by initscr with the  size
           of the screen.  The constants TRUE and FALSE have the val-
           ues 1 and 0, respectively.

           The curses routines also  define  the  WINDOW  *  variable
           curscr which is used for certain low-level operations like
           clearing and redrawing a screen containing  garbage.   The
           curscr can be used in only a few routines.

       Routine and Argument Names
           Many  curses routines have two or more versions.  The rou-
           tines prefixed with w require a window argument.  The rou-
           tines prefixed with p require a pad argument.  Those with-
           out a prefix generally use stdscr.

           The routines prefixed with mv require a y and x coordinate
           to  move to before performing the appropriate action.  The
           mv routines imply a call to move before the  call  to  the
           other  routine.  The coordinate y always refers to the row
           (of the window), and x always refers to the  column.   The
           upper left-hand corner is always (0,0), not (1,1).

           The routines prefixed with mvw take both a window argument
           and x and y coordinates.  The window  argument  is  always
           specified before the coordinates.

           In  each  case, win is the window affected, and pad is the

           Option setting routines require a Boolean flag bf with the
           value TRUE or FALSE; bf is always of type bool.  The vari-
           ables  ch  and attrs below are always of type chtype.  The
           types WINDOW, SCREEN, bool,  and  chtype  are  defined  in
           <curses.h>.   The  type  TERMINAL  is defined in <term.h>.
           All other arguments are integers.

       Routine Name Index
           The following table lists each curses routine and the name
           of  the  manual  page  on which it is described.  Routines
           flagged with `*' are ncurses-specific,  not  described  by
           XPG4 or present in SVr4.

           center  tab(/); l l l l .  curses Routine Name/Manual Page
           Name  =  addch/curs_addch(3X)  addchnstr/curs_addchstr(3X)
           addchstr/curs_addchstr(3X)         addnstr/curs_addstr(3X)
           addstr/curs_addstr(3X)               attroff/curs_attr(3X)
           attron/curs_attr(3X)       attrset/curs_attr(3X)      bau-
           drate/curs_termattrs(3X)                beep/curs_beep(3X)
           bkgd/curs_bkgd(3X)  bkgdset/curs_bkgd(3X) border/curs_bor-
           der(3X)                                box/curs_border(3X)
           can_change_color/curs_color(3X)     cbreak/curs_inopts(3X)
           clear/curs_clear(3X)    clearok/curs_outopts(3X)    clrto-
           bot/curs_clear(3X)    clrtoeol/curs_clear(3X)   color_con-
           tent/curs_color(3X)               copywin/curs_overlay(3X)
           curs_set/curs_kernel(3X)     def_prog_mode/curs_kernel(3X)
           def_shell_mode/curs_kernel(3X)       del_curterm/curs_ter-
           minfo(3X)  delay_output/curs_util(3X) delch/curs_delch(3X)
           deleteln/curs_deleteln(3X) delscreen/curs_initscr(3X) del-
           win/curs_window(3X)      derwin/curs_window(3X)      doup-
           date/curs_refresh(3X)               dupwin/curs_window(3X)
           echo/curs_inopts(3X)      echochar/curs_addch(3X)     end-
           win/curs_initscr(3X)                  erase/curs_clear(3X)
           erasechar/curs_termattrs(3X)          filter/curs_util(3X)
           flash/curs_beep(3X)     flushinp/curs_util(3X)      getbe-
           gyx/curs_getyx(3X)        getch/curs_getch(3X)        get-
           maxyx/curs_getyx(3X)     getmouse/curs_mouse(3X)*     get-
           paryx/curs_getyx(3X)      getstr/curs_getstr(3X)      get-
           syx/curs_kernel(3X)                   getwin/curs_util(3X)
           getyx/curs_getyx(3X)   halfdelay/curs_inopts(3X)  has_col-
           ors/curs_color(3X)               has_ic/curs_termattrs(3X)
           has_il/curs_termattrs(3X)          has_key/curs_getch(3X)*
           hline/curs_border(3X)               idcok/curs_outopts(3X)
           idlok/curs_outopts(3X)            immedok/curs_outopts(3X)
           inch/curs_inch(3X)     inchnstr/curs_inchstr(3X)     inch-
           str/curs_inchstr(3X)             init_color/curs_color(3X)
           init_pair/curs_color(3X)          initscr/curs_initscr(3X)
           innstr/curs_instr(3X)       insch/curs_insch(3X)      ins-
           delln/curs_deleteln(3X)         insertln/curs_deleteln(3X)
           insnstr/curs_insstr(3X)             insstr/curs_insstr(3X)
           isendwin/curs_initscr(3X)    keyname/curs_util(3X)    key-
           pad/curs_inopts(3X)            killchar/curs_termattrs(3X)
           leaveok/curs_outopts(3X)       longname/curs_termattrs(3X)
           mcprint/curs_print(3X)*  meta/curs_inopts(3X)  mouseinter-
           val/curs_mouse(3X)*              mousemask/curs_mouse(3X)*
           move/curs_move(3X)     mvaddch/curs_addch(3X)    mvaddchn-
           str/curs_addchstr(3X)         mvaddchstr/curs_addchstr(3X)
           mvaddnstr/curs_addstr(3X)         mvaddstr/curs_addstr(3X)
           mvcur/curs_terminfo(3X)   mvdelch/curs_delch(3X)    mvder-
           win/curs_window(3X)      mvgetch/curs_getch(3X)     mvget-
           str/curs_getstr(3X)     mvinch/curs_inch(3X)      mvinchn-
           str/curs_inchstr(3X)            mvinchstr/curs_inchstr(3X)
           mvinnstr/curs_instr(3X)    mvinsch/curs_insch(3X)    mvin-
           snstr/curs_insstr(3X)    mvinsstr/curs_insstr(3X)    mvin-
           str/curs_instr(3X)      mvprintw/curs_printw(3X)      mvs-
           canw/curs_scanw(3X)   mvwaddch/curs_addch(3X)   mvwaddchn-
           str/curs_addchstr(3X)        mvwaddchstr/curs_addchstr(3X)
           mvwaddnstr/curs_addstr(3X)       mvwaddstr/curs_addstr(3X)
           mvwdelch/curs_delch(3X)  mvwgetch/curs_getch(3X)   mvwget-
           str/curs_getstr(3X)                  mvwin/curs_window(3X)
           mvwinch/curs_inch(3X)         mvwinchnstr/curs_inchstr(3X)
           mvwinchstr/curs_inchstr(3X)       mvwinnstr/curs_instr(3X)
           mvwinsch/curs_insch(3X)         mvwinsnstr/curs_insstr(3X)
           mvwinsstr/curs_insstr(3X)   mvwinstr/curs_instr(3X)   mvw-
           printw/curs_printw(3X)             mvwscanw/curs_scanw(3X)
           napms/curs_kernel(3X)                  newpad/curs_pad(3X)
           newterm/curs_initscr(3X)            newwin/curs_window(3X)
           nl/curs_outopts(3X)     nocbreak/curs_inopts(3X)     node-
           lay/curs_inopts(3X) noecho/curs_inopts(3X)  nonl/curs_out-
           opts(3X)  noqiflush/curs_inopts(3X)  noraw/curs_inopts(3X)
           notimeout/curs_inopts(3X)  overlay/curs_overlay(3X)  over-
           write/curs_overlay(3X)         pair_content/curs_color(3X)
           pechochar/curs_pad(3X)   pnoutrefresh/curs_pad(3X)    pre-
           fresh/curs_pad(3X)  printw/curs_printw(3X)  putp/curs_ter-
           minfo(3X)   putwin/curs_util(3X)   qiflush/curs_inopts(3X)
           raw/curs_inopts(3X)             redrawwin/curs_refresh(3X)
           refresh/curs_refresh(3X)   reset_prog_mode/curs_kernel(3X)
           reset_shell_mode/curs_kernel(3X)   resetty/curs_kernel(3X)
           resizeterm/resizeterm(3X)*   restartterm/curs_terminfo(3X)
           ripoffline/curs_kernel(3X)         savetty/curs_kernel(3X)
           scanw/curs_scanw(3X)            scr_dump/curs_scr_dump(3X)
           scr_init/curs_scr_dump(3X)   scr_restore/curs_scr_dump(3X)
           scr_set/curs_scr_dump(3X)             scrl/curs_scroll(3X)
           scroll/curs_scroll(3X)           scrollok/curs_outopts(3X)
           set_curterm/curs_terminfo(3X)    set_term/curs_initscr(3X)
           setscrreg/curs_outopts(3X)   setsyx/curs_kernel(3X)   set-
           term/curs_terminfo(3X)         setupterm/curs_terminfo(3X)
           slk_attr/curs_slk(3X)*            slk_attroff/curs_slk(3X)
           slk_attron/curs_slk(3X)           slk_attrset/curs_slk(3X)
           slk_clear/curs_slk(3X)               slk_init/curs_slk(3X)
           slk_label/curs_slk(3X)        slk_noutrefresh/curs_slk(3X)
           slk_refresh/curs_slk(3X)          slk_restore/curs_slk(3X)
           start_color/curs_color(3X)    subpad/curs_pad(3X)     sub-
           win/curs_window(3X)     syncok/curs_window(3X)     termat-
           trs/curs_termattrs(3X)  termname/curs_termattrs(3X)   tge-
           tent/curs_termcap(3X)    tgetflag/curs_termcap(3X)   tget-
           num/curs_termcap(3X)              tgetstr/curs_termcap(3X)
           tgoto/curs_termcap(3X)  tigetflag/curs_terminfo(3X) tiget-
           num/curs_terminfo(3X)   tigetstr/curs_terminfo(3X)   time-
           out/curs_inopts(3X)     touchline/curs_touch(3X)    touch-
           win/curs_touch(3X)                 tparm/curs_terminfo(3X)
           tputs/curs_termcap(3X)    tputs/curs_terminfo(3X)   typea-
           head/curs_inopts(3X)                  unctrl/curs_util(3X)
           ungetch/curs_getch(3X) ungetmouse/curs_mouse(3X)* untouch-
           win/curs_touch(3X) use_env/curs_util(3X) vidattr/curs_ter-
           minfo(3X)  vidputs/curs_terminfo(3X) vline/curs_border(3X)
           vwprintw/curs_printw(3X)    vwscanw/curs_scanw(3X)    wad-
           dch/curs_addch(3X)   waddchnstr/curs_addchstr(3X)  waddch-
           str/curs_addchstr(3X)             waddnstr/curs_addstr(3X)
           waddstr/curs_addstr(3X)     wattroff/curs_attr(3X)    wat-
           tron/curs_attr(3X)                  wattrset/curs_attr(3X)
           wbkgd/curs_bkgd(3X)      wbkgdset/curs_bkgd(3X)      wbor-
           der/curs_border(3X)     wclear/curs_clear(3X)      wclrto-
           bot/curs_clear(3X)    wclrtoeol/curs_clear(3X)    wcursyn-
           cup/curs_window(3X)                  wdelch/curs_delch(3X)
           wdeleteln/curs_deleteln(3X)  wechochar/curs_addch(3X) wen-
           close/curs_mouse(3X)*                werase/curs_clear(3X)
           wgetch/curs_getch(3X)    wgetnstr/curs_getstr(3X)    wget-
           str/curs_getstr(3X)                 whline/curs_border(3X)
           winch/curs_inch(3X)    winchnstr/curs_inchstr(3X)   winch-
           str/curs_inchstr(3X)      winnstr/curs_instr(3X)      win-
           sch/curs_insch(3X)     winsdelln/curs_deleteln(3X)    win-
           sertln/curs_deleteln(3X)          winsnstr/curs_insstr(3X)
           winsstr/curs_insstr(3X)              winstr/curs_instr(3X)
           wmove/curs_move(3X)          wnoutrefresh/curs_refresh(3X)
           wprintw/curs_printw(3X)   wredrawln/curs_refresh(3X)  wre-
           fresh/curs_refresh(3X)                wresize/wresize(3X)*
           wscanw/curs_scanw(3X)    wscrl/curs_scroll(3X)    wsetscr-
           reg/curs_outopts(3X)    wstandend/curs_attr(3X)    wstand-
           out/curs_attr(3X)      wsyncdown/curs_window(3X)     wsyn-
           cup/curs_window(3X)               wtimeout/curs_inopts(3X)
           wtouchln/curs_touch(3X) wvline/curs_border(3X)

## RETURN VALUE

           Routines  that  return  an integer return ERR upon failure
           and an integer value other than ERR upon  successful  com-
           pletion,  unless  otherwise  noted in the routine descrip-
           tions.

           All macros return the  value  of  the  w  version,  except
           setscrreg,  wsetscrreg,  getyx,  getbegyx,  getmaxyx.  The
           return values of setscrreg, wsetscrreg,  getyx,  getbegyx,
           and getmaxyx are undefined (i.e., these should not be used
           as the right-hand side of assignment statements).

## SEE ALSO

           terminfo(5) and 3X pages whose  names  begin  "curs_"  for
           detailed routine descriptions.

## EXTENSIONS

           The curses library can be compiled with an option (-DTERM-
           CAP_FILE) that falls back to  the  old-style  /etc/termcap
           file  if  the  terminal  setup code cannot find a terminfo
           entry corresponding to TERM.  Use of this feature  is  not
           recommended,  as it essentially includes an entire termcap
           compiler in the curses startup code, at  significant  cost
           in core and startup cycles.

           Compiling  with  -DTERMCAP_FILE changes the library's ini-
           tialization sequence in a way intended to mimic the behav-
           ior of 4.4BSD curses.  If there is no local or system ter-
           minfo entry matching TERM,  then  the  library  looks  for
           termcap  entries  in the following places: (1) if TERMINFO
           is undefined, in the file named by  TERMCAP_FILE;  (2)  if
           TERMINFO  is defined and begins with a slash, it is inter-
           preted as the name of a termcap file to search  for  TERM;
           (3) otherwise, if TERMINFO has a leading string that looks
           like a terminal entry name list, and it matches TERM,  the
           contents  of  TERMINFO is interpreted as a termcap; (4) if
           TERMINFO looks like a termcap but doesn't match TERM,  the
           termcap  file  is  searched  for among the colon-separated
           paths in the environment variable  TERMPATHS  if  that  is
           defined,  and  in  ~/.termcap  and the file value of TERM-
           CAP_FILE otherwise.

           Versions of curses compiled on PC clones  support  display
           of  the  PC ROM characters (including ROM characters 0-31,
           which stock SVr4 curses cannot display).  See  the  EXTEN-
           SIONS sections of curs_addch(3X) and curs_attr(3X).

           The curses library includes facilities for capturing mouse
           events on certain terminals  (including  xterm).  See  the
           curs_mouse(3X) manual page for details.

           The  curses  library  includes  a  function  for directing
           application output to a printer attached to  the  terminal
           device.  See the curs_print(3X) manual page for details.

## PORTABILITY

           The curses library is intended to be BASE-level conformant
           with the XSI Curses standard.   Certain  portions  of  the
           EXTENDED  XSI  Curses  functionality (including color sup-
           port) are supported.  The following  EXTENDED  XSI  Curses
           calls  in  support  of wide (multibyte) characters are not
           yet implemented: addnwstr, addwstr, mvaddnwstr,  mvwaddnw-
           str,  mvaddwstr,  waddnwstr,  waddwstr, add_wch, wadd_wch,
           mvwadd_wchnstr,  mvwadd_wchstr,  bkgrndset,  bkgrnd,  get-
           bkgrnd, wbkgrnd, wbkgrndset, wgetbkgrnd, border_set, wbor-
           der_set,  box_set,  hline_set,  mvhline_set,  mvvline_set,
           mvwhline_set,    mvwvline_set,   whline_set,   vhline_set,
           wvline_set,  echo_wchar,  wecho_wchar,  erasewchar,  kill-
           wchar,    get_wch,    mvget_wch,    mvwget_ch,   wget_wch,
           getwchtype, get_wstr,  getn_wstr,  wget_wstr,  wgetn_wstr,
           mvget_wstr,  mvgetn_wstr, mvwget_wstr, mvwgetn_wstr, innw-
           str,  inwstr,  winnwstr,  winwstr,  mvinnwstr,   mvinwstr,
           mvwinnwstr,  mvwinwstr,  ins_nwstr, ins_wstr, mvins_nwstr,
           mvins_wstr,   mvwins_nwstr,    mvwins_wstr,    wins_nwstr,
           wins_wstr,   ins_wch,   wins_wch,  mvins_wch,  mvwins_wch,
           in_wch, win_wch, mvin_wch, mvwin_wch, inwchstr, inwchnstr,
           winwchstr,  winwchnstr,  mvinwchstr, mvinwchnstr, mvinwch-
           str, mvwinwchnstr.

           A small number of local differences (that  is,  individual
           differences  between  the XSI Curses and curses calls) are
           described in  PORTABILITY  sections  of  the  library  man
           pages.

           The routine has_key is not part of XPG4, nor is it present
           in SVr4.  See the curs_getch(3X) manual page for  details.

           The  routine  slk_attr is not part of XPG4, nor is it pre-
           sent in  SVr4.   See  the  curs_slk(3X)  manual  page  for
           details.

           The  routines getmouse, mousemask, ungetmouse, mouseinter-
           val, and wenclose relating to mouse  interfacing  are  not
           part  of  XPG4,  nor  are  they  present in SVr4.  See the
           curs_mouse(3X) manual page for details.

           The routine mcprint was not present in any previous curses
           implementation.   See  the  curs_print(3X) manual page for
           details.

           The routine wresize is not part of XPG4, nor is it present
           in SVr4.  See the wresize(3X) manual page for details.

           In  historic curses versions, delays embedded in the capa-
           bilities cr, ind, cub1, ff and tab activated corresponding
           delay  bits  in  the UNIX tty driver.  In this implementa-
           tion, all padding is done by NUL sends.   This  method  is
           slightly  more expensive, but narrows the interface to the
           UNIX kernel  significantly  and  increases  the  package's
           portability correspondingly.

           In  the  XSI  standard  and  SVr4 manual pages, many entry
           points have prototype arguments of the for char *const (or
           cchar_t  *const,  or  wchar_t  *const,  or  void  *const).
           Depending on one's interpretation of the ANSI  C  standard
           tion const char *x is a modifiable pointer to unmodifiable
           data, but char *const x' is  an  unmodifiable  pointer  to
           modifiable  data.  Given that C passes arguments by value,
           <type> *const as a formal type is at best  dubious.   Some
           compilers  choke  on  the  prototypes.  Therefore, in this
           implementation, they have been changed to const  <type>  *
           globally.

## NOTES

           The  header  file  <curses.h>  automatically  includes the
           header files <stdio.h> and <unctrl.h>.

           If standard output from a curses program is re-directed to
           something  which  is  not  a  tty,  screen updates will be
           directed to standard error.  This was an undocumented fea-
           ture of AT&T System V Release 3 curses.

## AUTHORS

           Zeyd  M.  Ben-Halim,  Eric  S. Raymond.  Descends from the
           original pcurses by Pavel Curtis.