           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 panels(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.

           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)
           baudrate               curs_termattrs(3X)
           beep                   curs_beep(3X)
           bkgd                   curs_bkgd(3X)
           bkgdset                curs_bkgd(3X)
           border                 curs_border(3X)
           box                    curs_border(3X)
           can_change_color       curs_color(3X)
           cbreak                 curs_inopts(3X)
           clear                  curs_clear(3X)
           clearok                curs_outopts(3X)
           clrtobot               curs_clear(3X)
           clrtoeol               curs_clear(3X)
           color_content          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_terminfo(3X)
           delay_output           curs_util(3X)
           delch                  curs_delch(3X)
           deleteln               curs_deleteln(3X)
           delscreen              curs_initscr(3X)
           delwin                 curs_window(3X)
           derwin                 curs_window(3X)
           doupdate               curs_refresh(3X)
           dupwin                 curs_window(3X)
           echo                   curs_inopts(3X)
           erase                  curs_clear(3X)
           erasechar              curs_termattrs(3X)
           filter                 curs_util(3X)
           flash                  curs_beep(3X)
           flushinp               curs_util(3X)
           getbegyx               curs_getyx(3X)
           getch                  curs_getch(3X)
           getmaxyx               curs_getyx(3X)
           getmouse               curs_mouse(3X)*
           getparyx               curs_getyx(3X)
           getstr                 curs_getstr(3X)
           getsyx                 curs_kernel(3X)
           getwin                 curs_util(3X)
           getyx                  curs_getyx(3X)
           halfdelay              curs_inopts(3X)
           has_colors             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)
           inchstr                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)
           insdelln               curs_deleteln(3X)
           insertln               curs_deleteln(3X)
           insnstr                curs_insstr(3X)
           insstr                 curs_insstr(3X)
           instr                  curs_instr(3X)
           intrflush              curs_inopts(3X)
           is_linetouched         curs_touch(3X)
           is_wintouched          curs_touch(3X)
           isendwin               curs_initscr(3X)
           keyname                curs_util(3X)
           keypad                 curs_inopts(3X)
           killchar               curs_termattrs(3X)
           leaveok                curs_outopts(3X)
           longname               curs_termattrs(3X)
           mcprint                curs_print(3X)*
           meta                   curs_inopts(3X)
           mouseinterval          curs_mouse(3X)*
           mousemask              curs_mouse(3X)*
           move                   curs_move(3X)
           mvaddch                curs_addch(3X)
           mvaddchnstr            curs_addchstr(3X)
           mvaddstr               curs_addstr(3X)
           mvcur                  curs_terminfo(3X)
           mvdelch                curs_delch(3X)
           mvderwin               curs_window(3X)
           mvgetch                curs_getch(3X)
           mvgetstr               curs_getstr(3X)
           mvinch                 curs_inch(3X)
           mvinchnstr             curs_inchstr(3X)
           mvinchstr              curs_inchstr(3X)
           mvinnstr               curs_instr(3X)
           mvinsch                curs_insch(3X)
           mvinsnstr              curs_insstr(3X)
           mvinsstr               curs_insstr(3X)
           mvinstr                curs_instr(3X)
           mvprintw               curs_printw(3X)
           mvscanw                curs_scanw(3X)
           mvwaddch               curs_addch(3X)
           mvwaddchnstr           curs_addchstr(3X)
           mvwaddchstr            curs_addchstr(3X)
           mvwaddnstr             curs_addstr(3X)
           mvwaddstr              curs_addstr(3X)
           mvwdelch               curs_delch(3X)
           mvwgetch               curs_getch(3X)
           mvwgetstr              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)
           mvwprintw              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)
           nodelay                curs_inopts(3X)
           noecho                 curs_inopts(3X)
           nonl                   curs_outopts(3X)
           noqiflush              curs_inopts(3X)
           noraw                  curs_inopts(3X)
           notimeout              curs_inopts(3X)
           overlay                curs_overlay(3X)
           overwrite              curs_overlay(3X)
           pair_content           curs_color(3X)
           pechochar              curs_pad(3X)
           pnoutrefresh           curs_pad(3X)
           putp                   curs_terminfo(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)
           setterm                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)
           slk_set                curs_slk(3X)
           slk_touch              curs_slk(3X)
           standend               curs_attr(3X)
           standout               curs_attr(3X)
           start_color            curs_color(3X)
           subpad                 curs_pad(3X)
           subwin                 curs_window(3X)
           syncok                 curs_window(3X)
           termattrs              curs_termattrs(3X)
           termname               curs_termattrs(3X)
           tgetent                curs_termcap(3X)
           tgetflag               curs_termcap(3X)
           tgetnum                curs_termcap(3X)
           tgetstr                curs_termcap(3X)
           tgoto                  curs_termcap(3X)
           tigetstr               curs_terminfo(3X)
           timeout                curs_inopts(3X)
           touchline              curs_touch(3X)
           touchwin               curs_touch(3X)
           tparm                  curs_terminfo(3X)
           tputs                  curs_termcap(3X)
           tputs                  curs_terminfo(3X)
           typeahead              curs_inopts(3X)
           unctrl                 curs_util(3X)
           ungetch                curs_getch(3X)
           ungetmouse             curs_mouse(3X)*
           untouchwin             curs_touch(3X)
           use_env                curs_util(3X)
           vidattr                curs_terminfo(3X)
           vidputs                curs_terminfo(3X)
           vline                  curs_border(3X)
           vwprintw               curs_printw(3X)
           vwscanw                curs_scanw(3X)
           waddch                 curs_addch(3X)
           waddchnstr             curs_addchstr(3X)
           waddchstr              curs_addchstr(3X)
           waddnstr               curs_addstr(3X)
           waddstr                curs_addstr(3X)
           wattroff               curs_attr(3X)
           wattron                curs_attr(3X)
           wattrset               curs_attr(3X)
           wbkgd                  curs_bkgd(3X)
           wbkgdset               curs_bkgd(3X)
           wborder                curs_border(3X)
           wclear                 curs_clear(3X)
           wclrtobot              curs_clear(3X)
           wclrtoeol              curs_clear(3X)
           wcursyncup             curs_window(3X)
           wdelch                 curs_delch(3X)
           wdeleteln              curs_deleteln(3X)
           wechochar              curs_addch(3X)
           wenclose               curs_mouse(3X)*
           werase                 curs_clear(3X)
           wgetch                 curs_getch(3X)
           wgetnstr               curs_getstr(3X)
           wgetstr                curs_getstr(3X)
           whline                 curs_border(3X)
           winch                  curs_inch(3X)
           winchnstr              curs_inchstr(3X)
           winchstr               curs_inchstr(3X)
           winnstr                curs_instr(3X)
           winsch                 curs_insch(3X)
           winsdelln              curs_deleteln(3X)
           winsertln              curs_deleteln(3X)
           winsnstr               curs_insstr(3X)
           winsstr                curs_insstr(3X)
           winstr                 curs_instr(3X)
           wprintw                curs_printw(3X)
           wredrawln              curs_refresh(3X)
           wrefresh               curs_refresh(3X)
           wresize                wresize(3x)*
           wscanw                 curs_scanw(3X)
           wscrl                  curs_scroll(3X)
           wsetscrreg             curs_outopts(3X)
           wstandend              curs_attr(3X)
           wstandout              curs_attr(3X)
           wsyncdown              curs_window(3X)
           wsyncup                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).

           Routines that return pointers return NULL on error.

## 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
           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,
           mvadd_wch, mvwadd_wch, add_wchnstr, add_wchstr, wadd_wchn-
           str,     wadd_wchstr,     mvadd_wchnstr,     mvadd_wchstr,
           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.

           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
           (see  section  3.5.4.1), these declarations are either (a)
           meaningless, or (b) meaningless and illegal.  The declara-
           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.