


ncurses(3)                                             ncurses(3)


NAME
       curses - 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(3) library of Sys-
       tem 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
       -lcurses option.

       The curses 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-
       minal should be set and  its  initialization  strings,  if
       defined,  must  be  output.  This can be done by executing
       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.]




                                                                1





ncurses(3)                                             ncurses(3)


       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(3) 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 curses 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(3) 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
       running  in an AT&T 630 layer, for example, where the size
       of a screen is changeable (see ENVIRONMENT).

       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



                                                                2





ncurses(3)                                             ncurses(3)


       TERM is set to att4424, then the compiled terminal defini-
       tion is found in

             /usr/share/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

             /usr/share/terminfo/a/att4424.

       This is useful for developing experimental definitions  or
       when write permission in /usr/share/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
       pad affected; win and pad are always pointers to type WIN-
       DOW.

       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



                                                                3





ncurses(3)                                             ncurses(3)


       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
               -------------------------------------------
               COLOR_PAIR              curs_color(3)
               PAIR_NUMBER             curs_attr(3)
               addch                   curs_addch(3)
               addchnstr               curs_addchstr(3)
               addchstr                curs_addchstr(3)
               addnstr                 curs_addstr(3)
               assume_default_colors   default_colors(3)*
               attr_get                curs_attr(3)
               attr_off                curs_attr(3)
               attr_on                 curs_attr(3)
               attr_set                curs_attr(3)
               addstr                  curs_addstr(3)
               attroff                 curs_attr(3)
               attron                  curs_attr(3)
               attrset                 curs_attr(3)
               baudrate                curs_termattrs(3)
               beep                    curs_beep(3)
               bkgd                    curs_bkgd(3)
               bkgdset                 curs_bkgd(3)
               border                  curs_border(3)
               box                     curs_border(3)
               can_change_color        curs_color(3)
               cbreak                  curs_inopts(3)
               chgat                   curs_attr(3)
               clear                   curs_clear(3)
               clearok                 curs_outopts(3)
               clrtobot                curs_clear(3)
               clrtoeol                curs_clear(3)
               color_content           curs_color(3)
               color_set               curs_attr(3)
               copywin                 curs_overlay(3)
               curs_set                curs_kernel(3)
               curses_version          curs_extend(3)*
               def_prog_mode           curs_kernel(3)
               def_shell_mode          curs_kernel(3)
               define_key              define_key(3)*
               del_curterm             terminfo(3)
               delay_output            curs_util(3)
               delch                   curs_delch(3)
               deleteln                curs_deleteln(3)




                                                                4





ncurses(3)                                             ncurses(3)


               delscreen               curs_initscr(3)
               delwin                  curs_window(3)
               derwin                  curs_window(3)
               doupdate                curs_refresh(3)
               dupwin                  curs_window(3)
               echo                    curs_inopts(3)
               echochar                curs_addch(3)
               endwin                  curs_initscr(3)
               erase                   curs_clear(3)
               erasechar               curs_termattrs(3)
               filter                  curs_util(3)
               flash                   curs_beep(3)
               flushinp                curs_util(3)
               getbegyx                curs_getyx(3)
               getbkgd                 curs_bkgd(3)
               getch                   curs_getch(3)
               getmaxyx                curs_getyx(3)
               getmouse                curs_mouse(3)*
               getnstr                 curs_getstr(3)
               getparyx                curs_getyx(3)
               getstr                  curs_getstr(3)
               getsyx                  curs_kernel(3)
               getwin                  curs_util(3)
               getyx                   curs_getyx(3)
               halfdelay               curs_inopts(3)
               has_colors              curs_color(3)
               has_ic                  curs_termattrs(3)
               has_il                  curs_termattrs(3)
               has_key                 curs_getch(3)*
               hline                   curs_border(3)
               idcok                   curs_outopts(3)
               idlok                   curs_outopts(3)
               immedok                 curs_outopts(3)
               inch                    curs_inch(3)
               inchnstr                curs_inchstr(3)
               inchstr                 curs_inchstr(3)
               init_color              curs_color(3)
               init_pair               curs_color(3)
               initscr                 curs_initscr(3)
               innstr                  curs_instr(3)
               insch                   curs_insch(3)
               insdelln                curs_deleteln(3)
               insertln                curs_deleteln(3)
               insnstr                 curs_insstr(3)
               insstr                  curs_insstr(3)
               instr                   curs_instr(3)
               intrflush               curs_inopts(3)
               is_linetouched          curs_touch(3)
               is_wintouched           curs_touch(3)
               isendwin                curs_initscr(3)
               keybound                keybound(3)*
               keyname                 curs_util(3)
               keyok                   keyok(3)*




                                                                5





ncurses(3)                                             ncurses(3)


               keypad                  curs_inopts(3)
               killchar                curs_termattrs(3)
               leaveok                 curs_outopts(3)
               longname                curs_termattrs(3)
               mcprint                 curs_print(3)*
               meta                    curs_inopts(3)
               mouse_trafo             curs_mouse(3)*
               mouseinterval           curs_mouse(3)*
               mousemask               curs_mouse(3)*
               move                    curs_move(3)
               mvaddch                 curs_addch(3)
               mvaddchnstr             curs_addchstr(3)
               mvaddchstr              curs_addchstr(3)
               mvaddnstr               curs_addstr(3)
               mvaddstr                curs_addstr(3)
               mvchgat                 curs_attr(3)
               mvcur                   terminfo(3)
               mvdelch                 curs_delch(3)
               mvderwin                curs_window(3)
               mvgetch                 curs_getch(3)
               mvgetnstr               curs_getstr(3)
               mvgetstr                curs_getstr(3)
               mvhline                 curs_border(3)
               mvinch                  curs_inch(3)
               mvinchnstr              curs_inchstr(3)
               mvinchstr               curs_inchstr(3)
               mvinnstr                curs_instr(3)
               mvinsch                 curs_insch(3)
               mvinsnstr               curs_insstr(3)
               mvinsstr                curs_insstr(3)
               mvinstr                 curs_instr(3)
               mvprintw                curs_printw(3)
               mvscanw                 curs_scanw(3)
               mvvline                 curs_border(3)
               mvwaddch                curs_addch(3)
               mvwaddchnstr            curs_addchstr(3)
               mvwaddchstr             curs_addchstr(3)
               mvwaddnstr              curs_addstr(3)
               mvwaddstr               curs_addstr(3)
               mvwchgat                curs_attr(3)
               mvwdelch                curs_delch(3)
               mvwgetch                curs_getch(3)
               mvwgetnstr              curs_getstr(3)
               mvwgetstr               curs_getstr(3)
               mvwhline                curs_border(3)
               mvwin                   curs_window(3)
               mvwinch                 curs_inch(3)
               mvwinchnstr             curs_inchstr(3)
               mvwinchstr              curs_inchstr(3)
               mvwinnstr               curs_instr(3)
               mvwinsch                curs_insch(3)
               mvwinsnstr              curs_insstr(3)
               mvwinsstr               curs_insstr(3)




                                                                6





ncurses(3)                                             ncurses(3)


               mvwinstr                curs_instr(3)
               mvwprintw               curs_printw(3)
               mvwscanw                curs_scanw(3)
               mvwvline                curs_border(3)
               napms                   curs_kernel(3)
               newpad                  curs_pad(3)
               newterm                 curs_initscr(3)
               newwin                  curs_window(3)
               nl                      curs_outopts(3)
               nocbreak                curs_inopts(3)
               nodelay                 curs_inopts(3)
               noecho                  curs_inopts(3)
               nonl                    curs_outopts(3)
               noqiflush               curs_inopts(3)
               noraw                   curs_inopts(3)
               notimeout               curs_inopts(3)
               overlay                 curs_overlay(3)
               overwrite               curs_overlay(3)
               pair_content            curs_color(3)
               pechochar               curs_pad(3)
               pnoutrefresh            curs_pad(3)
               prefresh                curs_pad(3)
               printw                  curs_printw(3)
               putp                    terminfo(3)
               putwin                  curs_util(3)
               qiflush                 curs_inopts(3)
               raw                     curs_inopts(3)
               redrawwin               curs_refresh(3)
               refresh                 curs_refresh(3)
               reset_prog_mode         curs_kernel(3)
               reset_shell_mode        curs_kernel(3)
               resetty                 curs_kernel(3)
               resizeterm              resizeterm(3)*
               restartterm             terminfo(3)
               ripoffline              curs_kernel(3)
               savetty                 curs_kernel(3)
               scanw                   curs_scanw(3)
               scr_dump                curs_scr_dump(3)
               scr_init                curs_scr_dump(3)
               scr_restore             curs_scr_dump(3)
               scr_set                 curs_scr_dump(3)
               scrl                    curs_scroll(3)
               scroll                  curs_scroll(3)
               scrollok                curs_outopts(3)
               set_curterm             terminfo(3)
               set_term                curs_initscr(3)
               setscrreg               curs_outopts(3)
               setsyx                  curs_kernel(3)
               setterm                 terminfo(3)
               setupterm               terminfo(3)
               slk_attr                curs_slk(3)*
               slk_attr_off            curs_slk(3)
               slk_attr_on             curs_slk(3)




                                                                7





ncurses(3)                                             ncurses(3)


               slk_attr_set            curs_slk(3)
               slk_attroff             curs_slk(3)
               slk_attron              curs_slk(3)
               slk_attrset             curs_slk(3)
               slk_clear               curs_slk(3)
               slk_color               curs_slk(3)
               slk_init                curs_slk(3)
               slk_label               curs_slk(3)
               slk_noutrefresh         curs_slk(3)
               slk_refresh             curs_slk(3)
               slk_restore             curs_slk(3)
               slk_set                 curs_slk(3)
               slk_touch               curs_slk(3)
               standend                curs_attr(3)
               standout                curs_attr(3)
               start_color             curs_color(3)
               subpad                  curs_pad(3)
               subwin                  curs_window(3)
               syncok                  curs_window(3)
               termattrs               curs_termattrs(3)
               termname                curs_termattrs(3)
               tgetent                 termcap(3)
               tgetflag                termcap(3)
               tgetnum                 termcap(3)
               tgetstr                 termcap(3)
               tgoto                   termcap(3)
               tigetflag               terminfo(3)
               tigetnum                terminfo(3)
               tigetstr                terminfo(3)
               timeout                 curs_inopts(3)
               touchline               curs_touch(3)
               touchwin                curs_touch(3)
               tparm                   terminfo(3)
               tputs                   termcap(3)
               tputs                   terminfo(3)
               typeahead               curs_inopts(3)
               unctrl                  curs_util(3)
               ungetch                 curs_getch(3)
               ungetmouse              curs_mouse(3)*
               untouchwin              curs_touch(3)
               use_default_colors      default_colors(3)*
               use_env                 curs_util(3)
               use_extended_names      curs_extend(3)*
               vidattr                 terminfo(3)
               vidputs                 terminfo(3)
               vline                   curs_border(3)
               vw_printw               curs_printw(3)
               vw_scanw                curs_scanw(3)
               vwprintw                curs_printw(3)
               vwscanw                 curs_scanw(3)
               waddch                  curs_addch(3)
               waddchnstr              curs_addchstr(3)
               waddchstr               curs_addchstr(3)




                                                                8





ncurses(3)                                             ncurses(3)


               waddnstr                curs_addstr(3)
               waddstr                 curs_addstr(3)
               wattr_get               curs_attr(3)
               wattr_off               curs_attr(3)
               wattr_on                curs_attr(3)
               wattr_set               curs_attr(3)
               wattroff                curs_attr(3)
               wattron                 curs_attr(3)
               wattrset                curs_attr(3)
               wbkgd                   curs_bkgd(3)
               wbkgdset                curs_bkgd(3)
               wborder                 curs_border(3)
               wchgat                  curs_attr(3)
               wclear                  curs_clear(3)
               wclrtobot               curs_clear(3)
               wclrtoeol               curs_clear(3)
               wcolor_set              curs_attr(3)
               wcursyncup              curs_window(3)
               wdelch                  curs_delch(3)
               wdeleteln               curs_deleteln(3)
               wechochar               curs_addch(3)
               wenclose                curs_mouse(3)*
               werase                  curs_clear(3)
               wgetch                  curs_getch(3)
               wgetnstr                curs_getstr(3)
               wgetstr                 curs_getstr(3)
               whline                  curs_border(3)
               winch                   curs_inch(3)
               winchnstr               curs_inchstr(3)
               winchstr                curs_inchstr(3)
               winnstr                 curs_instr(3)
               winsch                  curs_insch(3)
               winsdelln               curs_deleteln(3)
               winsertln               curs_deleteln(3)
               winsnstr                curs_insstr(3)
               winsstr                 curs_insstr(3)
               winstr                  curs_instr(3)
               wmouse_trafo            curs_mouse(3)*
               wmove                   curs_move(3)
               wnoutrefresh            curs_refresh(3)
               wprintw                 curs_printw(3)
               wredrawln               curs_refresh(3)
               wrefresh                curs_refresh(3)
               wresize                 wresize(3)*
               wscanw                  curs_scanw(3)
               wscrl                   curs_scroll(3)
               wsetscrreg              curs_outopts(3)
               wstandend               curs_attr(3)
               wstandout               curs_attr(3)
               wsyncdown               curs_window(3)
               wsyncup                 curs_window(3)
               wtimeout                curs_inopts(3)
               wtouchln                curs_touch(3)




                                                                9





ncurses(3)                                             ncurses(3)


               wvline                  curs_border(3)

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, and 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.

ENVIRONMENT
       The following environment symbols are useful for customiz-
       ing the runtime behavior of the curses library.  The  most
       important ones have already been discussed in detail.

       BAUDRATE
            The  debugging library checks this environment symbol
            when the application has redirected output to a file.
            The  symbol's numeric value is used for the baudrate.
            If no value is found, curses uses 9600.  This  allows
            testers  to construct repeatable test-cases that take
            into account costs that depend on baudrate.

       CC   When set, change occurrences of the command_character
            (i.e.,  the  cmdch capability) of the loaded terminfo
            entries to the value of this symbol.  Very  few  ter-
            minfo entries provide this feature.

       COLUMNS
            Specify  the  width  of  the  screen  in  characters.
            Applications running in a windowing environment  usu-
            ally  are  able  to obtain the width of the window in
            which they are executing.  If  neither  the  $COLUMNS
            value  nor  the  terminal's screen size is available,
            curses uses the size which may be  specified  in  the
            terminfo database (i.e., the cols capability).

            It  is  important that your application use a correct
            size for the screen.  However,  this  is  not  always
            possible because your application may be running on a
            host which does not honor  NAWS  (Negotiations  About
            Window  Size), or because you are temporarily running
            as another user.

            Either COLUMNS or  LINES  symbols  may  be  specified
            independently.   This  is mainly useful to circumvent
            legacy misfeatures of  terminal  descriptions,  e.g.,
            xterm which commonly specifies a 65 line screen.  For



                                                               10





ncurses(3)                                             ncurses(3)


            best results, lines and cols should not be  specified
            in a terminal description for terminals which are run
            as emulations.

            Use the use_env function to disable this feature.

       ESCDELAY
            Specifies the total time, in milliseconds, for  which
            curses will await a character sequence, e.g., a func-
            tion key.  The default value, 1000  milliseconds,  is
            enough for most uses.  However, it is made a variable
            to accommodate unusual applications.

            The most common instance where you may wish to change
            this  value is to work with slow hosts, e.g., running
            on a network.  If the  host  cannot  read  characters
            rapidly  enough,  it  will have the same effect as if
            the terminal did not send characters rapidly  enough.
            The library will still see a timeout.

            Note  that xterm mouse events are built up from char-
            acter sequences received from  the  xterm.   If  your
            application makes heavy use of multiple-clicking, you
            may wish to lengthen this default value  because  the
            timeout  applies to the composed multi-click event as
            well as the individual clicks.

       HOME Tells curses where your home directory is.   That  is
            where  it  may  read  and  write  auxiliary  terminal
            descriptions:

            $HOME/.termcap
            $HOME/.terminfo

       LINES
            Like COLUMNS, specify the height  of  the  screen  in
            characters.   See COLUMNS for a detailed description.

       MOUSE_BUTTONS_123
            This applies only to the OS/2 EMX port.  It specifies
            the  order  of  buttons on the mouse.  OS/2 numbers a
            3-button mouse inconsistently from other platforms:

            1 = left
            2 = right
            3 = middle.

            This symbol lets you customize the mouse.  The symbol
            must  be three numeric digits 1-3 in any order, e.g.,
            123 or 321.  If it is not specified, curses uses 132.

       NCURSES_NO_PADDING
            Most  of  the  terminal  descriptions in the terminfo
            database are written for real  "hardware"  terminals.



                                                               11





ncurses(3)                                             ncurses(3)


            Many  people  use  terminal  emulators which run in a
            windowing environment and use  curses-based  applica-
            tions.   Terminal  emulators can duplicate all of the
            important aspects of a hardware terminal, but they do
            not  have the same limitations.  The chief limitation
            of a hardware terminal from the  standpoint  of  your
            application is the management of dataflow, i.e., tim-
            ing.  Unless a hardware terminal is interfaced into a
            terminal  concentrator  (which does flow control), it
            (or your application) must manage dataflow,  prevent-
            ing  overruns.   The  cheapest  solution (no hardware
            cost) is for your program to do this by pausing after
            operations  that  the  terminal  does slowly, such as
            clearing the display.

            As a result, many  terminal  descriptions  (including
            the  vt100)  have delay times embedded.  You may wish
            to use these descriptions, but not want  to  pay  the
            performance penalty.

            Set  the NCURSES_NO_PADDING symbol to disable all but
            mandatory padding.  Mandatory padding is  used  as  a
            part of special control sequences such as flash.

       NCURSES_NO_SETBUF
            Normally curses enables buffered output during termi-
            nal initialization.  This is done (as in SVr4 curses)
            for  performance reasons.  For testing purposes, both
            of curses and certain applications, this  feature  is
            made  optional.   Setting the NCURSES_NO_SETBUF vari-
            able disables output buffering, leaving the output in
            the original (usually line buffered) mode.

       NCURSES_TRACE
            During  initialization,  the curses debugging library
            checks the NCURSES_TRACE symbol.  If it  is  defined,
            to  a numeric value, curses calls the trace function,
            using that value as the argument.

            The argument values, which are defined  in  curses.h,
            provide  several  types of information.  When running
            with traces enabled, your application will write  the
            file trace to the current directory.

       TERM Denotes  your  terminal  type.  Each terminal type is
            distinct, though many are similar.

       TERMCAP
            If the curses library has been configured with  term-
            cap  support,  curses  will  check  for  a terminal's
            description in termcap form if it is not available in
            the terminfo database.

            The   TERMCAP   symbol  contains  either  a  terminal



                                                               12





ncurses(3)                                             ncurses(3)


            description (with newlines stripped out), or  a  file
            name  telling  where  the  information denoted by the
            TERM symbol  exists.   In  either  case,  setting  it
            directs  curses  to  ignore  the usual place for this
            information, e.g., /etc/termcap.

       TERMINFO
            Overrides the directory in which curses searches  for
            your terminal description.  This is the simplest, but
            not the only way to change the list  of  directories.
            The complete list of directories in order follows:

            -  the  last directory to which curses wrote, if any,
               is searched first

            -  the directory specified by the TERMINFO symbol

            -  $HOME/.terminfo

            -  directories listed in the TERMINFO_DIRS symbol

            -  one or more directories whose names are configured
               and   compiled  into  the  curses  library,  e.g.,
               /usr/share/terminfo

       TERMINFO_DIRS
            Specifies a list of directories to search for  termi-
            nal  descriptions.   The  list is separated by colons
            (i.e., ":").  All of the terminal descriptions are in
            terminfo  form,  which makes a subdirectory named for
            the first letter of the terminal names therein.

       TERMPATH
            If TERMCAP does not hold  a  file  name  then  curses
            checks  the TERMPATH symbol.  This is a list of file-
            names  separated  by  colons  (i.e.,  ":").   If  the
            TERMPATH symbol is not set, curses looks in the files
            /etc/termcap, /usr/share/termcap and  $HOME/.termcap,
            in that order.

       The  library  will  disregard the following variables when
       the application uses setuid or setgid permissions:  $TERM-
       CAP,  $TERMINFO,  $TERMINFO_DIRS,  $TERMPATH,  as  well as
       $HOME.

FILES
       /usr/share/tabset
            directory containing  initialization  files  for  the
            terminal capability database /usr/share/terminfo ter-
            minal capability database

SEE ALSO
       terminfo(5), terminfo(3), and 3 pages  whose  names  begin
       with "curs_" for detailed routine descriptions.



                                                               13





ncurses(3)                                             ncurses(3)


       /usr/share/doc/html/curses/ncurses-intro.html
              intro to ncurses.

       /usr/share/doc/html/curses/hackguide.html
              ncurses hacker's guide.

EXTENSIONS
       The   curses  library  can  be  compiled  with  an  option
       (-DUSE_GETCAP) that falls back to the old-style /etc/term-
       cap 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.

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

       The  curses  library includes facilities for responding to
       window resizing events, e.g., when running  in  an  xterm.
       See  the  resizeterm(3)  and  wresize(3)  manual pages for
       details.  In addition, the library may be configured  with
       a SIGWINCH handler.

       The  curses  library extends the fixed set of function key
       capabilities of  terminals  by  allowing  the  application
       designer  to  define  additional key sequences at runtime.
       See  the  define_key(3)  and  keyok(3)  manual  pages  for
       details.

       The  curses library can exploit the capabilities of termi-
       nals which implement the ISO-6429 SGR 39 and SGR  49  con-
       trols, which allow an application to reset the terminal to
       its original foreground and background colors.   From  the
       users'  perspective,  the application is able to draw col-
       ored text on a background  whose  color  is  set  indepen-
       dently,  providing  better  control  over color contrasts.
       See the use_default_colors(3) 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(3) 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: add_wch, add_wchnstr, add_wchstr, addnw-
       str,  addwstr,  bkgrnd,  bkgrndset,  border_set,  box_set,
       echo_wchar,   erasewchar,  get_wch,  get_wstr,  getbkgrnd,
       getcchar,  getn_wstr,   getwchtype,   hline_set,   in_wch,



                                                               14





ncurses(3)                                             ncurses(3)


       in_wchnstr,   in_wchstr,   innwstr,   ins_nwstr,  ins_wch,
       ins_wstr, inwchnstr,  inwchstr,  inwstr,  key_name,  kill-
       wchar, mvadd_wch, mvadd_wchnstr, mvadd_wchstr, mvaddnwstr,
       mvaddwstr,  mvget_wch,   mvget_wstr,   mvgetn_wstr,   mvh-
       line_set,  mvin_wch,  mvinnwstr,  mvins_nwstr,  mvins_wch,
       mvins_wstr, mvinwchnstr, mvinwchstr, mvinwchstr, mvinwstr,
       mvvline_set,  mvwadd_wch,  mvwadd_wchnstr,  mvwadd_wchstr,
       mvwaddnwstr,    mvwaddwstr,     mvwget_ch,     mvwget_wch,
       mvwget_wstr,    mvwgetn_wstr,   mvwhline_set,   mvwin_wch,
       mvwin_wchnstr,  mvwin_wchstr,  mvwinnwstr,   mvwins_nwstr,
       mvwins_wch,  mvwins_wstr,  mvwinwchnstr,  mvwinwstr, mvwv-
       line_set,  pecho_wchar,  setcchar,  slk_wset,  term_attrs,
       unget_wch,   vhline_set,  vid_attr,  vid_puts,  vline_set,
       wadd_wch, wadd_wchnstr, wadd_wchstr, waddnwstr,  waddwstr,
       waddwstr,  wbkgrnd,  wbkgrndset,  wbkgrndset, wborder_set,
       wecho_wchar, wecho_wchar, wget_wch, wget_wstr, wgetbkgrnd,
       wgetn_wstr,  whline_set, win_wch, win_wchnstr, win_wchstr,
       winnwstr,  wins_nwstr,  wins_wch,  wins_wstr,  winwchnstr,
       winwchstr, winwstr, wunctrl, wvline_set,

       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(3) manual page for details.

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

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

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



                                                               15





ncurses(3)                                             ncurses(3)


       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, Thomas E. Dickey.
       Based on pcurses by Pavel Curtis.

































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