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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 libraries, 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 configuration 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 applications. 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 mutexes for their respective WINDOW and SCREEN parameters, and call a user-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 altered 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 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 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) 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) 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 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_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 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 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_VERSION.
SEE ALSO curses(3X), curs_opaque(3X), curs_variables(3X).
curs_threads(3X)