# curs_threads 3x

    curs_threads(3x)                                              curs_threads(3x)

## NAME

           curs_threads - curses thread support

## SYNOPSIS

           #include <curses.h>

           typedef int (*NCURSES_WINDOW_CB)(WINDOW *, void *);
           typedef int (*NCURSES_SCREEN_CB)(SCREEN *, void *);

           int get_escdelay(void);
           int set_escdelay(int ms);
           int set_tabsize(int cols);

           int use_screen(SCREEN *scr, NCURSES_SCREEN_CB func, void *data);
           int use_window(WINDOW *win, NCURSES_WINDOW_CB func, void *data);

## DESCRIPTION

           This  implementation  can  be configured to provide rudimentary support
           for multi-threaded applications.  This makes a  different  set  of  li-
           braries, e.g., libncursest since the binary interfaces are different.

           Rather  than  modify  the interfaces to pass a thread specifier to each
           function, it adds a few functions which can be used in  any  configura-
           tion  which  hide  the  mutex's needed to prevent concurrent use of the
           global variables when configured for threading.

           In addition to forcing access to members of the WINDOW structure to  be
           via  functions  (see curs_opaque(3x)), it makes functions of the common
           global variables, e.g., COLORS,  COLOR_PAIRS,  COLS,  ESCDELAY,  LINES,
           TABSIZE  curscr, newscr and ttytype.  Those variables are maintained as
           read-only values, stored in the SCREEN structure.

           Even this is not enough to make a thread-safe application using curses.
           A multi-threaded application would be expected to have threads updating
           separate windows (within the same  device),  or  updating  on  separate
           screens  (on  different  devices).  Also, a few of the global variables
           are considered writable by some applications.  The functions  described
           here address these special situations.

           The ESCDELAY and TABSIZE global variables are modified by some applica-
           tions.  To modify them in any configuration, use  the  set_escdelay  or
           set_tabsize functions.  Other global variables are not modifiable.

           The get_escdelay function returns the value for ESCDELAY.

           The  use_window and use_screen functions provide coarse granularity mu-
           texes for their respective WINDOW and SCREEN parameters, and call a us-
           er-supplied  function,  passing  it a data parameter, and returning the
           value from the user-supplied function to the application.

### USAGE

           All of the ncurses library functions assume that the locale is not  al-
           tered during operation.  In addition, they use data which is maintained
           within a hierarchy of scopes.

              o   global data, e.g., used in the low-level terminfo or termcap in-
                  terfaces.

              o   terminal data, e.g., associated with a call to set_curterm.  The
                  terminal data are initialized when screens are created.

              o   screen data, e.g., associated with a call to newterm or initscr.

              o   window data, e.g., associated with a call to newwin  or  subwin.
                  Windows  are  associated with screens.  Pads are not necessarily
                  associated with a particular screen.

                  Most curses applications operate on one or more windows within a
                  single screen.

              o   reentrant, i.e., it uses only the data passed as parameters.

           This  table lists the scope of data used for each symbol in the ncurses
           library when it is configured to support threading:

                Symbol                  Scope
                -------------------------------------------------------------
                BC                      global
                COLORS                  screen (readonly)
                COLOR_PAIR              reentrant
                COLOR_PAIRS             screen (readonly)
                COLS                    screen (readonly)
                ESCDELAY                screen (readonly, see set_escdelay)
                LINES                   screen (readonly)
                PAIR_NUMBER             reentrant
                PC                      global
                SP                      global
                TABSIZE                 screen (readonly)
                UP                      global
                acs_map                 screen (readonly)
                add_wch                 window (stdscr)
                add_wchnstr             window (stdscr)
                add_wchstr              window (stdscr)
                addch                   window (stdscr)
                addchnstr               window (stdscr)
                addchstr                window (stdscr)
                addnstr                 window (stdscr)
                addnwstr                window (stdscr)
                addstr                  window (stdscr)
                addwstr                 window (stdscr)
                assume_default_colors   screen
                attr_get                window (stdscr)
                attr_off                window (stdscr)
                attr_on                 window (stdscr)
                attr_set                window (stdscr)
                attroff                 window (stdscr)
                attron                  window (stdscr)
                attrset                 window (stdscr)
                baudrate                screen
                beep                    screen
                bkgd                    window (stdscr)
                bkgdset                 window (stdscr)
                bkgrnd                  window (stdscr)
                bkgrndset               window (stdscr)
                boolcodes               global (readonly)
                boolfnames              global (readonly)
                boolnames               global (readonly)
                border                  window (stdscr)
                border_set              window (stdscr)
                box                     window (stdscr)
                box_set                 window (stdscr)
                can_change_color        terminal
                cbreak                  screen
                chgat                   window (stdscr)
                clear                   window (stdscr)
                clearok                 window
                clrtobot                window (stdscr)
                clrtoeol                window (stdscr)
                color_content           screen

                color_set               window (stdscr)
                copywin                 window locks(source, target)
                cur_term                terminal
                curs_set                screen
                curscr                  screen (readonly)
                curses_version          global (readonly)
                def_prog_mode           terminal
                def_shell_mode          terminal
                define_key              screen
                del_curterm             screen
                delay_output            screen
                delch                   window (stdscr)
                deleteln                window (stdscr)
                delscreen               global locks(screenlist, screen)
                delwin                  global locks(windowlist)
                derwin                  screen
                doupdate                screen
                dupwin                  screen locks(window)
                echo                    screen
                echo_wchar              window (stdscr)
                echochar                window (stdscr)
                endwin                  screen
                erase                   window (stdscr)
                erasechar               window (stdscr)
                erasewchar              window (stdscr)
                filter                  global
                flash                   terminal
                flushinp                screen
                get_wch                 screen (input-operation)
                get_wstr                screen (input-operation)
                getattrs                window
                getbegx                 window
                getbegy                 window
                getbkgd                 window
                getbkgrnd               window
                getcchar                reentrant
                getch                   screen (input-operation)
                getcurx                 window
                getcury                 window
                getmaxx                 window
                getmaxy                 window
                getmouse                screen (input-operation)
                getn_wstr               screen (input-operation)
                getnstr                 screen (input-operation)
                getparx                 window
                getpary                 window
                getstr                  screen (input-operation)
                getwin                  screen (input-operation)
                halfdelay               screen
                has_colors              terminal
                has_ic                  terminal
                has_il                  terminal
                has_key                 screen
                hline                   window (stdscr)
                hline_set               window (stdscr)
                idcok                   window
                idlok                   window
                immedok                 window
                in_wch                  window (stdscr)
                in_wchnstr              window (stdscr)
                in_wchstr               window (stdscr)
                inch                    window (stdscr)
                inchnstr                window (stdscr)
                inchstr                 window (stdscr)
                init_color              screen
                init_pair               screen

                initscr                 global locks(screenlist)
                innstr                  window (stdscr)
                innwstr                 window (stdscr)
                ins_nwstr               window (stdscr)
                ins_wch                 window (stdscr)
                ins_wstr                window (stdscr)
                insch                   window (stdscr)
                insdelln                window (stdscr)
                insertln                window (stdscr)
                insnstr                 window (stdscr)
                insstr                  window (stdscr)
                instr                   window (stdscr)
                intrflush               terminal
                inwstr                  window (stdscr)
                is_cleared              window
                is_idcok                window
                is_idlok                window
                is_immedok              window
                is_keypad               window
                is_leaveok              window
                is_linetouched          window
                is_nodelay              window
                is_notimeout            window
                is_scrollok             window
                is_syncok               window
                is_term_resized         terminal
                is_wintouched           window
                isendwin                screen
                key_defined             screen
                key_name                global (static data)
                keybound                screen
                keyname                 global (static data)
                keyok                   screen
                keypad                  window
                killchar                terminal
                killwchar               terminal
                leaveok                 window
                longname                screen
                mcprint                 terminal
                meta                    screen
                mouse_trafo             window (stdscr)
                mouseinterval           screen
                mousemask               screen
                move                    window (stdscr)
                mvadd_wch               window (stdscr)
                mvadd_wchnstr           window (stdscr)
                mvadd_wchstr            window (stdscr)
                mvaddch                 window (stdscr)
                mvaddchnstr             window (stdscr)
                mvaddchstr              window (stdscr)
                mvaddnstr               window (stdscr)
                mvaddnwstr              window (stdscr)
                mvaddstr                window (stdscr)
                mvaddwstr               window (stdscr)
                mvchgat                 window (stdscr)
                mvcur                   screen
                mvdelch                 window (stdscr)
                mvderwin                window (stdscr)
                mvget_wch               screen (input-operation)
                mvget_wstr              screen (input-operation)
                mvgetch                 screen (input-operation)
                mvgetn_wstr             screen (input-operation)
                mvgetnstr               screen (input-operation)
                mvgetstr                screen (input-operation)
                mvhline                 window (stdscr)
                mvhline_set             window (stdscr)

                mvin_wch                window (stdscr)
                mvin_wchnstr            window (stdscr)
                mvin_wchstr             window (stdscr)
                mvinch                  window (stdscr)
                mvinchnstr              window (stdscr)
                mvinchstr               window (stdscr)
                mvinnstr                window (stdscr)
                mvinnwstr               window (stdscr)
                mvins_nwstr             window (stdscr)
                mvins_wch               window (stdscr)
                mvins_wstr              window (stdscr)
                mvinsch                 window (stdscr)
                mvinsnstr               window (stdscr)
                mvinsstr                window (stdscr)
                mvinstr                 window (stdscr)
                mvinwstr                window (stdscr)
                mvprintw                window (stdscr)
                mvscanw                 screen
                mvvline                 window (stdscr)
                mvvline_set             window (stdscr)
                mvwadd_wch              window
                mvwadd_wchnstr          window
                mvwadd_wchstr           window
                mvwaddch                window
                mvwaddchnstr            window
                mvwaddchstr             window
                mvwaddnstr              window
                mvwaddnwstr             window
                mvwaddstr               window
                mvwaddwstr              window
                mvwchgat                window
                mvwdelch                window
                mvwget_wch              screen (input-operation)
                mvwget_wstr             screen (input-operation)
                mvwgetch                screen (input-operation)
                mvwgetn_wstr            screen (input-operation)
                mvwgetnstr              screen (input-operation)
                mvwgetstr               screen (input-operation)
                mvwhline                window
                mvwhline_set            window
                mvwin                   window
                mvwin_wch               window
                mvwin_wchnstr           window
                mvwin_wchstr            window
                mvwinch                 window
                mvwinchnstr             window
                mvwinchstr              window
                mvwinnstr               window
                mvwinnwstr              window
                mvwins_nwstr            window
                mvwins_wch              window
                mvwins_wstr             window
                mvwinsch                window
                mvwinsnstr              window
                mvwinsstr               window
                mvwinstr                window
                mvwinwstr               window
                mvwprintw               window
                mvwscanw                screen
                mvwvline                window
                mvwvline_set            window
                napms                   reentrant
                newpad                  global locks(windowlist)
                newscr                  screen (readonly)
                newterm                 global locks(screenlist)
                newwin                  global locks(windowlist)

                nl                      screen
                nocbreak                screen
                nodelay                 window
                noecho                  screen
                nofilter                global
                nonl                    screen
                noqiflush               terminal
                noraw                   screen
                notimeout               window
                numcodes                global (readonly)
                numfnames               global (readonly)
                numnames                global (readonly)
                ospeed                  global
                overlay                 window locks(source, target)
                overwrite               window locks(source, target)
                pair_content            screen
                pecho_wchar             screen
                pechochar               screen
                pnoutrefresh            screen
                prefresh                screen
                printw                  window
                putp                    global
                putwin                  window
                qiflush                 terminal
                raw                     screen
                redrawwin               window
                refresh                 screen
                reset_prog_mode         screen
                reset_shell_mode        screen
                resetty                 terminal
                resize_term             screen locks(windowlist)
                resizeterm              screen
                restartterm             screen
                ripoffline              global (static data)
                savetty                 terminal
                scanw                   screen
                scr_dump                screen
                scr_init                screen
                scr_restore             screen
                scr_set                 screen
                scrl                    window (stdscr)
                scroll                  window
                scrollok                window
                set_curterm             screen
                set_escdelay            screen
                set_tabsize             screen
                set_term                global locks(screenlist, screen)
                setcchar                reentrant
                setscrreg               window (stdscr)
                setupterm               global
                slk_attr                screen
                slk_attr_off            screen
                slk_attr_on             screen
                slk_attr_set            screen
                slk_attroff             screen
                slk_attron              screen
                slk_attrset             screen
                slk_clear               screen
                slk_color               screen
                slk_init                screen
                slk_label               screen
                slk_noutrefresh         screen
                slk_refresh             screen
                slk_restore             screen
                slk_set                 screen
                slk_touch               screen

                slk_wset                screen
                standend                window
                standout                window
                start_color             screen
                stdscr                  screen (readonly)
                strcodes                global (readonly)
                strfnames               global (readonly)
                strnames                global (readonly)
                subpad                  window
                subwin                  window
                syncok                  window
                term_attrs              screen
                termattrs               screen
                termname                terminal
                tgetent                 global
                tgetflag                global
                tgetnum                 global
                tgetstr                 global
                tgoto                   global
                tigetflag               terminal
                tigetnum                terminal
                tigetstr                terminal
                timeout                 window (stdscr)
                touchline               window
                touchwin                window
                tparm                   global (static data)
                tputs                   screen
                trace                   global (static data)
                ttytype                 screen (readonly)
                typeahead               screen
                unctrl                  screen
                unget_wch               screen (input-operation)
                ungetch                 screen (input-operation)
                ungetmouse              screen (input-operation)
                untouchwin              window
                use_default_colors      screen
                use_env                 global (static data)
                use_extended_names      global (static data)
                use_legacy_coding       screen
                use_screen              global locks(screenlist, screen)
                use_window              global locks(windowlist, window)
                vid_attr                screen
                vid_puts                screen
                vidattr                 screen
                vidputs                 screen
                vline                   window (stdscr)
                vline_set               window (stdscr)
                vw_printw               window
                vw_scanw                screen
                vwprintw                window
                vwscanw                 screen
                wadd_wch                window
                wadd_wchnstr            window
                wadd_wchstr             window
                waddch                  window
                waddchnstr              window
                waddchstr               window
                waddnstr                window
                waddnwstr               window
                waddstr                 window
                waddwstr                window
                wattr_get               window
                wattr_off               window
                wattr_on                window
                wattr_set               window
                wattroff                window

                wattron                 window
                wattrset                window
                wbkgd                   window
                wbkgdset                window
                wbkgrnd                 window
                wbkgrndset              window
                wborder                 window
                wborder_set             window
                wchgat                  window
                wclear                  window
                wclrtobot               window
                wclrtoeol               window
                wcolor_set              window
                wcursyncup              screen (affects window plus parents)
                wdelch                  window
                wdeleteln               window
                wecho_wchar             window
                wechochar               window
                wenclose                window
                werase                  window
                wget_wch                screen (input-operation)
                wget_wstr               screen (input-operation)
                wgetbkgrnd              window
                wgetch                  screen (input-operation)
                wgetdelay               window
                wgetn_wstr              screen (input-operation)
                wgetnstr                screen (input-operation)
                wgetparent              window
                wgetscrreg              window
                wgetstr                 screen (input-operation)
                whline                  window
                whline_set              window
                win_wch                 window
                win_wchnstr             window
                win_wchstr              window
                winch                   window
                winchnstr               window
                winchstr                window
                winnstr                 window
                winnwstr                window
                wins_nwstr              window
                wins_wch                window
                wins_wstr               window
                winsch                  window
                winsdelln               window
                winsertln               window
                winsnstr                window
                winsstr                 window
                winstr                  window
                winwstr                 window
                wmouse_trafo            window
                wmove                   window
                wnoutrefresh            screen
                wprintw                 window
                wredrawln               window
                wrefresh                screen
                wresize                 window locks(windowlist)
                wscanw                  screen
                wscrl                   window
                wsetscrreg              window
                wstandend               window
                wstandout               window
                wsyncdown               screen (affects window plus parents)
                wsyncup                 screen (affects window plus parents)
                wtimeout                window
                wtouchln                window

                wunctrl                 global (static data)
                wvline                  window
                wvline_set              window

## RETURN VALUE

           These functions all return TRUE or FALSE, except as noted.

## NOTES

           Both a macro and a function are provided for each name.

## PORTABILITY

           These routines are specific to ncurses.  They  were  not  supported  on
           Version 7, BSD or System V implementations.  It is recommended that any
           code depending on ncurses extensions be conditioned using  NCURSES_VER-
           SION.

## SEE ALSO

           curses(3x), curs_opaque(3x), curs_variables(3x).

                                                                  curs_threads(3x)