1:mod:`curses` --- Terminal handling for character-cell displays 2=============================================================== 3 4.. module:: curses 5 :synopsis: An interface to the curses library, providing portable 6 terminal handling. 7 :platform: Unix 8 9.. sectionauthor:: Moshe Zadka <moshez@zadka.site.co.il> 10.. sectionauthor:: Eric Raymond <esr@thyrsus.com> 11 12-------------- 13 14The :mod:`curses` module provides an interface to the curses library, the 15de-facto standard for portable advanced terminal handling. 16 17While curses is most widely used in the Unix environment, versions are available 18for Windows, DOS, and possibly other systems as well. This extension module is 19designed to match the API of ncurses, an open-source curses library hosted on 20Linux and the BSD variants of Unix. 21 22.. note:: 23 24 Whenever the documentation mentions a *character* it can be specified 25 as an integer, a one-character Unicode string or a one-byte byte string. 26 27 Whenever the documentation mentions a *character string* it can be specified 28 as a Unicode string or a byte string. 29 30.. note:: 31 32 Since version 5.4, the ncurses library decides how to interpret non-ASCII data 33 using the ``nl_langinfo`` function. That means that you have to call 34 :func:`locale.setlocale` in the application and encode Unicode strings 35 using one of the system's available encodings. This example uses the 36 system's default encoding:: 37 38 import locale 39 locale.setlocale(locale.LC_ALL, '') 40 code = locale.getpreferredencoding() 41 42 Then use *code* as the encoding for :meth:`str.encode` calls. 43 44.. seealso:: 45 46 Module :mod:`curses.ascii` 47 Utilities for working with ASCII characters, regardless of your locale settings. 48 49 Module :mod:`curses.panel` 50 A panel stack extension that adds depth to curses windows. 51 52 Module :mod:`curses.textpad` 53 Editable text widget for curses supporting :program:`Emacs`\ -like bindings. 54 55 :ref:`curses-howto` 56 Tutorial material on using curses with Python, by Andrew Kuchling and Eric 57 Raymond. 58 59 The :source:`Tools/demo/` directory in the Python source distribution contains 60 some example programs using the curses bindings provided by this module. 61 62 63.. _curses-functions: 64 65Functions 66--------- 67 68The module :mod:`curses` defines the following exception: 69 70 71.. exception:: error 72 73 Exception raised when a curses library function returns an error. 74 75.. note:: 76 77 Whenever *x* or *y* arguments to a function or a method are optional, they 78 default to the current cursor location. Whenever *attr* is optional, it defaults 79 to :const:`A_NORMAL`. 80 81The module :mod:`curses` defines the following functions: 82 83 84.. function:: baudrate() 85 86 Return the output speed of the terminal in bits per second. On software 87 terminal emulators it will have a fixed high value. Included for historical 88 reasons; in former times, it was used to write output loops for time delays and 89 occasionally to change interfaces depending on the line speed. 90 91 92.. function:: beep() 93 94 Emit a short attention sound. 95 96 97.. function:: can_change_color() 98 99 Return ``True`` or ``False``, depending on whether the programmer can change the colors 100 displayed by the terminal. 101 102 103.. function:: cbreak() 104 105 Enter cbreak mode. In cbreak mode (sometimes called "rare" mode) normal tty 106 line buffering is turned off and characters are available to be read one by one. 107 However, unlike raw mode, special characters (interrupt, quit, suspend, and flow 108 control) retain their effects on the tty driver and calling program. Calling 109 first :func:`raw` then :func:`cbreak` leaves the terminal in cbreak mode. 110 111 112.. function:: color_content(color_number) 113 114 Return the intensity of the red, green, and blue (RGB) components in the color 115 *color_number*, which must be between ``0`` and ``COLORS - 1``. Return a 3-tuple, 116 containing the R,G,B values for the given color, which will be between 117 ``0`` (no component) and ``1000`` (maximum amount of component). 118 119 120.. function:: color_pair(pair_number) 121 122 Return the attribute value for displaying text in the specified color pair. 123 Only the first 256 color pairs are supported. This 124 attribute value can be combined with :const:`A_STANDOUT`, :const:`A_REVERSE`, 125 and the other :const:`A_\*` attributes. :func:`pair_number` is the counterpart 126 to this function. 127 128 129.. function:: curs_set(visibility) 130 131 Set the cursor state. *visibility* can be set to ``0``, ``1``, or ``2``, for invisible, 132 normal, or very visible. If the terminal supports the visibility requested, return the 133 previous cursor state; otherwise raise an exception. On many 134 terminals, the "visible" mode is an underline cursor and the "very visible" mode 135 is a block cursor. 136 137 138.. function:: def_prog_mode() 139 140 Save the current terminal mode as the "program" mode, the mode when the running 141 program is using curses. (Its counterpart is the "shell" mode, for when the 142 program is not in curses.) Subsequent calls to :func:`reset_prog_mode` will 143 restore this mode. 144 145 146.. function:: def_shell_mode() 147 148 Save the current terminal mode as the "shell" mode, the mode when the running 149 program is not using curses. (Its counterpart is the "program" mode, when the 150 program is using curses capabilities.) Subsequent calls to 151 :func:`reset_shell_mode` will restore this mode. 152 153 154.. function:: delay_output(ms) 155 156 Insert an *ms* millisecond pause in output. 157 158 159.. function:: doupdate() 160 161 Update the physical screen. The curses library keeps two data structures, one 162 representing the current physical screen contents and a virtual screen 163 representing the desired next state. The :func:`doupdate` ground updates the 164 physical screen to match the virtual screen. 165 166 The virtual screen may be updated by a :meth:`~window.noutrefresh` call after write 167 operations such as :meth:`~window.addstr` have been performed on a window. The normal 168 :meth:`~window.refresh` call is simply :meth:`!noutrefresh` followed by :func:`!doupdate`; 169 if you have to update multiple windows, you can speed performance and perhaps 170 reduce screen flicker by issuing :meth:`!noutrefresh` calls on all windows, 171 followed by a single :func:`!doupdate`. 172 173 174.. function:: echo() 175 176 Enter echo mode. In echo mode, each character input is echoed to the screen as 177 it is entered. 178 179 180.. function:: endwin() 181 182 De-initialize the library, and return terminal to normal status. 183 184 185.. function:: erasechar() 186 187 Return the user's current erase character as a one-byte bytes object. Under Unix operating systems this 188 is a property of the controlling tty of the curses program, and is not set by 189 the curses library itself. 190 191 192.. function:: filter() 193 194 The :func:`.filter` routine, if used, must be called before :func:`initscr` is 195 called. The effect is that, during those calls, :envvar:`LINES` is set to ``1``; the 196 capabilities ``clear``, ``cup``, ``cud``, ``cud1``, ``cuu1``, ``cuu``, ``vpa`` are disabled; and the ``home`` 197 string is set to the value of ``cr``. The effect is that the cursor is confined to 198 the current line, and so are screen updates. This may be used for enabling 199 character-at-a-time line editing without touching the rest of the screen. 200 201 202.. function:: flash() 203 204 Flash the screen. That is, change it to reverse-video and then change it back 205 in a short interval. Some people prefer such as 'visible bell' to the audible 206 attention signal produced by :func:`beep`. 207 208 209.. function:: flushinp() 210 211 Flush all input buffers. This throws away any typeahead that has been typed 212 by the user and has not yet been processed by the program. 213 214 215.. function:: getmouse() 216 217 After :meth:`~window.getch` returns :const:`KEY_MOUSE` to signal a mouse event, this 218 method should be called to retrieve the queued mouse event, represented as a 219 5-tuple ``(id, x, y, z, bstate)``. *id* is an ID value used to distinguish 220 multiple devices, and *x*, *y*, *z* are the event's coordinates. (*z* is 221 currently unused.) *bstate* is an integer value whose bits will be set to 222 indicate the type of event, and will be the bitwise OR of one or more of the 223 following constants, where *n* is the button number from 1 to 4: 224 :const:`BUTTONn_PRESSED`, :const:`BUTTONn_RELEASED`, :const:`BUTTONn_CLICKED`, 225 :const:`BUTTONn_DOUBLE_CLICKED`, :const:`BUTTONn_TRIPLE_CLICKED`, 226 :const:`BUTTON_SHIFT`, :const:`BUTTON_CTRL`, :const:`BUTTON_ALT`. 227 228 229.. function:: getsyx() 230 231 Return the current coordinates of the virtual screen cursor as a tuple 232 ``(y, x)``. If :meth:`leaveok <window.leaveok>` is currently ``True``, then return ``(-1, -1)``. 233 234 235.. function:: getwin(file) 236 237 Read window related data stored in the file by an earlier :func:`putwin` call. 238 The routine then creates and initializes a new window using that data, returning 239 the new window object. 240 241 242.. function:: has_colors() 243 244 Return ``True`` if the terminal can display colors; otherwise, return ``False``. 245 246 247.. function:: has_ic() 248 249 Return ``True`` if the terminal has insert- and delete-character capabilities. 250 This function is included for historical reasons only, as all modern software 251 terminal emulators have such capabilities. 252 253 254.. function:: has_il() 255 256 Return ``True`` if the terminal has insert- and delete-line capabilities, or can 257 simulate them using scrolling regions. This function is included for 258 historical reasons only, as all modern software terminal emulators have such 259 capabilities. 260 261 262.. function:: has_key(ch) 263 264 Take a key value *ch*, and return ``True`` if the current terminal type recognizes 265 a key with that value. 266 267 268.. function:: halfdelay(tenths) 269 270 Used for half-delay mode, which is similar to cbreak mode in that characters 271 typed by the user are immediately available to the program. However, after 272 blocking for *tenths* tenths of seconds, raise an exception if nothing has 273 been typed. The value of *tenths* must be a number between ``1`` and ``255``. Use 274 :func:`nocbreak` to leave half-delay mode. 275 276 277.. function:: init_color(color_number, r, g, b) 278 279 Change the definition of a color, taking the number of the color to be changed 280 followed by three RGB values (for the amounts of red, green, and blue 281 components). The value of *color_number* must be between ``0`` and 282 `COLORS - 1`. Each of *r*, *g*, *b*, must be a value between ``0`` and 283 ``1000``. When :func:`init_color` is used, all occurrences of that color on the 284 screen immediately change to the new definition. This function is a no-op on 285 most terminals; it is active only if :func:`can_change_color` returns ``True``. 286 287 288.. function:: init_pair(pair_number, fg, bg) 289 290 Change the definition of a color-pair. It takes three arguments: the number of 291 the color-pair to be changed, the foreground color number, and the background 292 color number. The value of *pair_number* must be between ``1`` and 293 ``COLOR_PAIRS - 1`` (the ``0`` color pair is wired to white on black and cannot 294 be changed). The value of *fg* and *bg* arguments must be between ``0`` and 295 ``COLORS - 1``, or, after calling :func:`use_default_colors`, ``-1``. 296 If the color-pair was previously initialized, the screen is 297 refreshed and all occurrences of that color-pair are changed to the new 298 definition. 299 300 301.. function:: initscr() 302 303 Initialize the library. Return a :ref:`window <curses-window-objects>` object 304 which represents the whole screen. 305 306 .. note:: 307 308 If there is an error opening the terminal, the underlying curses library may 309 cause the interpreter to exit. 310 311 312.. function:: is_term_resized(nlines, ncols) 313 314 Return ``True`` if :func:`resize_term` would modify the window structure, 315 ``False`` otherwise. 316 317 318.. function:: isendwin() 319 320 Return ``True`` if :func:`endwin` has been called (that is, the curses library has 321 been deinitialized). 322 323 324.. function:: keyname(k) 325 326 Return the name of the key numbered *k* as a bytes object. The name of a key generating printable 327 ASCII character is the key's character. The name of a control-key combination 328 is a two-byte bytes object consisting of a caret (``b'^'``) followed by the corresponding 329 printable ASCII character. The name of an alt-key combination (128--255) is a 330 bytes object consisting of the prefix ``b'M-'`` followed by the name of the corresponding 331 ASCII character. 332 333 334.. function:: killchar() 335 336 Return the user's current line kill character as a one-byte bytes object. Under Unix operating systems 337 this is a property of the controlling tty of the curses program, and is not set 338 by the curses library itself. 339 340 341.. function:: longname() 342 343 Return a bytes object containing the terminfo long name field describing the current 344 terminal. The maximum length of a verbose description is 128 characters. It is 345 defined only after the call to :func:`initscr`. 346 347 348.. function:: meta(flag) 349 350 If *flag* is ``True``, allow 8-bit characters to be input. If 351 *flag* is ``False``, allow only 7-bit chars. 352 353 354.. function:: mouseinterval(interval) 355 356 Set the maximum time in milliseconds that can elapse between press and release 357 events in order for them to be recognized as a click, and return the previous 358 interval value. The default value is 200 msec, or one fifth of a second. 359 360 361.. function:: mousemask(mousemask) 362 363 Set the mouse events to be reported, and return a tuple ``(availmask, 364 oldmask)``. *availmask* indicates which of the specified mouse events can be 365 reported; on complete failure it returns ``0``. *oldmask* is the previous value of 366 the given window's mouse event mask. If this function is never called, no mouse 367 events are ever reported. 368 369 370.. function:: napms(ms) 371 372 Sleep for *ms* milliseconds. 373 374 375.. function:: newpad(nlines, ncols) 376 377 Create and return a pointer to a new pad data structure with the given number 378 of lines and columns. Return a pad as a window object. 379 380 A pad is like a window, except that it is not restricted by the screen size, and 381 is not necessarily associated with a particular part of the screen. Pads can be 382 used when a large window is needed, and only a part of the window will be on the 383 screen at one time. Automatic refreshes of pads (such as from scrolling or 384 echoing of input) do not occur. The :meth:`~window.refresh` and :meth:`~window.noutrefresh` 385 methods of a pad require 6 arguments to specify the part of the pad to be 386 displayed and the location on the screen to be used for the display. The 387 arguments are *pminrow*, *pmincol*, *sminrow*, *smincol*, *smaxrow*, *smaxcol*; the *p* 388 arguments refer to the upper left corner of the pad region to be displayed and 389 the *s* arguments define a clipping box on the screen within which the pad region 390 is to be displayed. 391 392 393.. function:: newwin(nlines, ncols) 394 newwin(nlines, ncols, begin_y, begin_x) 395 396 Return a new :ref:`window <curses-window-objects>`, whose left-upper corner 397 is at ``(begin_y, begin_x)``, and whose height/width is *nlines*/*ncols*. 398 399 By default, the window will extend from the specified position to the lower 400 right corner of the screen. 401 402 403.. function:: nl() 404 405 Enter newline mode. This mode translates the return key into newline on input, 406 and translates newline into return and line-feed on output. Newline mode is 407 initially on. 408 409 410.. function:: nocbreak() 411 412 Leave cbreak mode. Return to normal "cooked" mode with line buffering. 413 414 415.. function:: noecho() 416 417 Leave echo mode. Echoing of input characters is turned off. 418 419 420.. function:: nonl() 421 422 Leave newline mode. Disable translation of return into newline on input, and 423 disable low-level translation of newline into newline/return on output (but this 424 does not change the behavior of ``addch('\n')``, which always does the 425 equivalent of return and line feed on the virtual screen). With translation 426 off, curses can sometimes speed up vertical motion a little; also, it will be 427 able to detect the return key on input. 428 429 430.. function:: noqiflush() 431 432 When the :func:`!noqiflush` routine is used, normal flush of input and output queues 433 associated with the ``INTR``, ``QUIT`` and ``SUSP`` characters will not be done. You may 434 want to call :func:`!noqiflush` in a signal handler if you want output to 435 continue as though the interrupt had not occurred, after the handler exits. 436 437 438.. function:: noraw() 439 440 Leave raw mode. Return to normal "cooked" mode with line buffering. 441 442 443.. function:: pair_content(pair_number) 444 445 Return a tuple ``(fg, bg)`` containing the colors for the requested color pair. 446 The value of *pair_number* must be between ``0`` and ``COLOR_PAIRS - 1``. 447 448 449.. function:: pair_number(attr) 450 451 Return the number of the color-pair set by the attribute value *attr*. 452 :func:`color_pair` is the counterpart to this function. 453 454 455.. function:: putp(str) 456 457 Equivalent to ``tputs(str, 1, putchar)``; emit the value of a specified 458 terminfo capability for the current terminal. Note that the output of :func:`putp` 459 always goes to standard output. 460 461 462.. function:: qiflush([flag]) 463 464 If *flag* is ``False``, the effect is the same as calling :func:`noqiflush`. If 465 *flag* is ``True``, or no argument is provided, the queues will be flushed when 466 these control characters are read. 467 468 469.. function:: raw() 470 471 Enter raw mode. In raw mode, normal line buffering and processing of 472 interrupt, quit, suspend, and flow control keys are turned off; characters are 473 presented to curses input functions one by one. 474 475 476.. function:: reset_prog_mode() 477 478 Restore the terminal to "program" mode, as previously saved by 479 :func:`def_prog_mode`. 480 481 482.. function:: reset_shell_mode() 483 484 Restore the terminal to "shell" mode, as previously saved by 485 :func:`def_shell_mode`. 486 487 488.. function:: resetty() 489 490 Restore the state of the terminal modes to what it was at the last call to 491 :func:`savetty`. 492 493 494.. function:: resize_term(nlines, ncols) 495 496 Backend function used by :func:`resizeterm`, performing most of the work; 497 when resizing the windows, :func:`resize_term` blank-fills the areas that are 498 extended. The calling application should fill in these areas with 499 appropriate data. The :func:`!resize_term` function attempts to resize all 500 windows. However, due to the calling convention of pads, it is not possible 501 to resize these without additional interaction with the application. 502 503 504.. function:: resizeterm(nlines, ncols) 505 506 Resize the standard and current windows to the specified dimensions, and 507 adjusts other bookkeeping data used by the curses library that record the 508 window dimensions (in particular the SIGWINCH handler). 509 510 511.. function:: savetty() 512 513 Save the current state of the terminal modes in a buffer, usable by 514 :func:`resetty`. 515 516 517.. function:: setsyx(y, x) 518 519 Set the virtual screen cursor to *y*, *x*. If *y* and *x* are both ``-1``, then 520 :meth:`leaveok <window.leaveok>` is set ``True``. 521 522 523.. function:: setupterm(term=None, fd=-1) 524 525 Initialize the terminal. *term* is a string giving 526 the terminal name, or ``None``; if omitted or ``None``, the value of the 527 :envvar:`TERM` environment variable will be used. *fd* is the 528 file descriptor to which any initialization sequences will be sent; if not 529 supplied or ``-1``, the file descriptor for ``sys.stdout`` will be used. 530 531 532.. function:: start_color() 533 534 Must be called if the programmer wants to use colors, and before any other color 535 manipulation routine is called. It is good practice to call this routine right 536 after :func:`initscr`. 537 538 :func:`start_color` initializes eight basic colors (black, red, green, yellow, 539 blue, magenta, cyan, and white), and two global variables in the :mod:`curses` 540 module, :const:`COLORS` and :const:`COLOR_PAIRS`, containing the maximum number 541 of colors and color-pairs the terminal can support. It also restores the colors 542 on the terminal to the values they had when the terminal was just turned on. 543 544 545.. function:: termattrs() 546 547 Return a logical OR of all video attributes supported by the terminal. This 548 information is useful when a curses program needs complete control over the 549 appearance of the screen. 550 551 552.. function:: termname() 553 554 Return the value of the environment variable :envvar:`TERM`, as a bytes object, 555 truncated to 14 characters. 556 557 558.. function:: tigetflag(capname) 559 560 Return the value of the Boolean capability corresponding to the terminfo 561 capability name *capname* as an integer. Return the value ``-1`` if *capname* is not a 562 Boolean capability, or ``0`` if it is canceled or absent from the terminal 563 description. 564 565 566.. function:: tigetnum(capname) 567 568 Return the value of the numeric capability corresponding to the terminfo 569 capability name *capname* as an integer. Return the value ``-2`` if *capname* is not a 570 numeric capability, or ``-1`` if it is canceled or absent from the terminal 571 description. 572 573 574.. function:: tigetstr(capname) 575 576 Return the value of the string capability corresponding to the terminfo 577 capability name *capname* as a bytes object. Return ``None`` if *capname* 578 is not a terminfo "string capability", or is canceled or absent from the 579 terminal description. 580 581 582.. function:: tparm(str[, ...]) 583 584 Instantiate the bytes object *str* with the supplied parameters, where *str* should 585 be a parameterized string obtained from the terminfo database. E.g. 586 ``tparm(tigetstr("cup"), 5, 3)`` could result in ``b'\033[6;4H'``, the exact 587 result depending on terminal type. 588 589 590.. function:: typeahead(fd) 591 592 Specify that the file descriptor *fd* be used for typeahead checking. If *fd* 593 is ``-1``, then no typeahead checking is done. 594 595 The curses library does "line-breakout optimization" by looking for typeahead 596 periodically while updating the screen. If input is found, and it is coming 597 from a tty, the current update is postponed until refresh or doupdate is called 598 again, allowing faster response to commands typed in advance. This function 599 allows specifying a different file descriptor for typeahead checking. 600 601 602.. function:: unctrl(ch) 603 604 Return a bytes object which is a printable representation of the character *ch*. 605 Control characters are represented as a caret followed by the character, for 606 example as ``b'^C'``. Printing characters are left as they are. 607 608 609.. function:: ungetch(ch) 610 611 Push *ch* so the next :meth:`~window.getch` will return it. 612 613 .. note:: 614 615 Only one *ch* can be pushed before :meth:`!getch` is called. 616 617 618.. function:: update_lines_cols() 619 620 Update :envvar:`LINES` and :envvar:`COLS`. Useful for detecting manual screen resize. 621 622 .. versionadded:: 3.5 623 624 625.. function:: unget_wch(ch) 626 627 Push *ch* so the next :meth:`~window.get_wch` will return it. 628 629 .. note:: 630 631 Only one *ch* can be pushed before :meth:`!get_wch` is called. 632 633 .. versionadded:: 3.3 634 635 636.. function:: ungetmouse(id, x, y, z, bstate) 637 638 Push a :const:`KEY_MOUSE` event onto the input queue, associating the given 639 state data with it. 640 641 642.. function:: use_env(flag) 643 644 If used, this function should be called before :func:`initscr` or newterm are 645 called. When *flag* is ``False``, the values of lines and columns specified in the 646 terminfo database will be used, even if environment variables :envvar:`LINES` 647 and :envvar:`COLUMNS` (used by default) are set, or if curses is running in a 648 window (in which case default behavior would be to use the window size if 649 :envvar:`LINES` and :envvar:`COLUMNS` are not set). 650 651 652.. function:: use_default_colors() 653 654 Allow use of default values for colors on terminals supporting this feature. Use 655 this to support transparency in your application. The default color is assigned 656 to the color number ``-1``. After calling this function, ``init_pair(x, 657 curses.COLOR_RED, -1)`` initializes, for instance, color pair *x* to a red 658 foreground color on the default background. 659 660 661.. function:: wrapper(func, ...) 662 663 Initialize curses and call another callable object, *func*, which should be the 664 rest of your curses-using application. If the application raises an exception, 665 this function will restore the terminal to a sane state before re-raising the 666 exception and generating a traceback. The callable object *func* is then passed 667 the main window 'stdscr' as its first argument, followed by any other arguments 668 passed to :func:`!wrapper`. Before calling *func*, :func:`!wrapper` turns on 669 cbreak mode, turns off echo, enables the terminal keypad, and initializes colors 670 if the terminal has color support. On exit (whether normally or by exception) 671 it restores cooked mode, turns on echo, and disables the terminal keypad. 672 673 674.. _curses-window-objects: 675 676Window Objects 677-------------- 678 679Window objects, as returned by :func:`initscr` and :func:`newwin` above, have 680the following methods and attributes: 681 682 683.. method:: window.addch(ch[, attr]) 684 window.addch(y, x, ch[, attr]) 685 686 Paint character *ch* at ``(y, x)`` with attributes *attr*, overwriting any 687 character previously painted at that location. By default, the character 688 position and attributes are the current settings for the window object. 689 690 .. note:: 691 692 Writing outside the window, subwindow, or pad raises a :exc:`curses.error`. 693 Attempting to write to the lower right corner of a window, subwindow, 694 or pad will cause an exception to be raised after the character is printed. 695 696 697.. method:: window.addnstr(str, n[, attr]) 698 window.addnstr(y, x, str, n[, attr]) 699 700 Paint at most *n* characters of the character string *str* at 701 ``(y, x)`` with attributes 702 *attr*, overwriting anything previously on the display. 703 704 705.. method:: window.addstr(str[, attr]) 706 window.addstr(y, x, str[, attr]) 707 708 Paint the character string *str* at ``(y, x)`` with attributes 709 *attr*, overwriting anything previously on the display. 710 711 .. note:: 712 713 * Writing outside the window, subwindow, or pad raises :exc:`curses.error`. 714 Attempting to write to the lower right corner of a window, subwindow, 715 or pad will cause an exception to be raised after the string is printed. 716 717 * A `bug in ncurses <https://bugs.python.org/issue35924>`_, the backend 718 for this Python module, can cause SegFaults when resizing windows. This 719 is fixed in ncurses-6.1-20190511. If you are stuck with an earlier 720 ncurses, you can avoid triggering this if you do not call :func:`addstr` 721 with a *str* that has embedded newlines. Instead, call :func:`addstr` 722 separately for each line. 723 724 725.. method:: window.attroff(attr) 726 727 Remove attribute *attr* from the "background" set applied to all writes to the 728 current window. 729 730 731.. method:: window.attron(attr) 732 733 Add attribute *attr* from the "background" set applied to all writes to the 734 current window. 735 736 737.. method:: window.attrset(attr) 738 739 Set the "background" set of attributes to *attr*. This set is initially 740 ``0`` (no attributes). 741 742 743.. method:: window.bkgd(ch[, attr]) 744 745 Set the background property of the window to the character *ch*, with 746 attributes *attr*. The change is then applied to every character position in 747 that window: 748 749 * The attribute of every character in the window is changed to the new 750 background attribute. 751 752 * Wherever the former background character appears, it is changed to the new 753 background character. 754 755 756.. method:: window.bkgdset(ch[, attr]) 757 758 Set the window's background. A window's background consists of a character and 759 any combination of attributes. The attribute part of the background is combined 760 (OR'ed) with all non-blank characters that are written into the window. Both 761 the character and attribute parts of the background are combined with the blank 762 characters. The background becomes a property of the character and moves with 763 the character through any scrolling and insert/delete line/character operations. 764 765 766.. method:: window.border([ls[, rs[, ts[, bs[, tl[, tr[, bl[, br]]]]]]]]) 767 768 Draw a border around the edges of the window. Each parameter specifies the 769 character to use for a specific part of the border; see the table below for more 770 details. 771 772 .. note:: 773 774 A ``0`` value for any parameter will cause the default character to be used for 775 that parameter. Keyword parameters can *not* be used. The defaults are listed 776 in this table: 777 778 +-----------+---------------------+-----------------------+ 779 | Parameter | Description | Default value | 780 +===========+=====================+=======================+ 781 | *ls* | Left side | :const:`ACS_VLINE` | 782 +-----------+---------------------+-----------------------+ 783 | *rs* | Right side | :const:`ACS_VLINE` | 784 +-----------+---------------------+-----------------------+ 785 | *ts* | Top | :const:`ACS_HLINE` | 786 +-----------+---------------------+-----------------------+ 787 | *bs* | Bottom | :const:`ACS_HLINE` | 788 +-----------+---------------------+-----------------------+ 789 | *tl* | Upper-left corner | :const:`ACS_ULCORNER` | 790 +-----------+---------------------+-----------------------+ 791 | *tr* | Upper-right corner | :const:`ACS_URCORNER` | 792 +-----------+---------------------+-----------------------+ 793 | *bl* | Bottom-left corner | :const:`ACS_LLCORNER` | 794 +-----------+---------------------+-----------------------+ 795 | *br* | Bottom-right corner | :const:`ACS_LRCORNER` | 796 +-----------+---------------------+-----------------------+ 797 798 799.. method:: window.box([vertch, horch]) 800 801 Similar to :meth:`border`, but both *ls* and *rs* are *vertch* and both *ts* and 802 *bs* are *horch*. The default corner characters are always used by this function. 803 804 805.. method:: window.chgat(attr) 806 window.chgat(num, attr) 807 window.chgat(y, x, attr) 808 window.chgat(y, x, num, attr) 809 810 Set the attributes of *num* characters at the current cursor position, or at 811 position ``(y, x)`` if supplied. If *num* is not given or is ``-1``, 812 the attribute will be set on all the characters to the end of the line. This 813 function moves cursor to position ``(y, x)`` if supplied. The changed line 814 will be touched using the :meth:`touchline` method so that the contents will 815 be redisplayed by the next window refresh. 816 817 818.. method:: window.clear() 819 820 Like :meth:`erase`, but also cause the whole window to be repainted upon next 821 call to :meth:`refresh`. 822 823 824.. method:: window.clearok(flag) 825 826 If *flag* is ``True``, the next call to :meth:`refresh` will clear the window 827 completely. 828 829 830.. method:: window.clrtobot() 831 832 Erase from cursor to the end of the window: all lines below the cursor are 833 deleted, and then the equivalent of :meth:`clrtoeol` is performed. 834 835 836.. method:: window.clrtoeol() 837 838 Erase from cursor to the end of the line. 839 840 841.. method:: window.cursyncup() 842 843 Update the current cursor position of all the ancestors of the window to 844 reflect the current cursor position of the window. 845 846 847.. method:: window.delch([y, x]) 848 849 Delete any character at ``(y, x)``. 850 851 852.. method:: window.deleteln() 853 854 Delete the line under the cursor. All following lines are moved up by one line. 855 856 857.. method:: window.derwin(begin_y, begin_x) 858 window.derwin(nlines, ncols, begin_y, begin_x) 859 860 An abbreviation for "derive window", :meth:`derwin` is the same as calling 861 :meth:`subwin`, except that *begin_y* and *begin_x* are relative to the origin 862 of the window, rather than relative to the entire screen. Return a window 863 object for the derived window. 864 865 866.. method:: window.echochar(ch[, attr]) 867 868 Add character *ch* with attribute *attr*, and immediately call :meth:`refresh` 869 on the window. 870 871 872.. method:: window.enclose(y, x) 873 874 Test whether the given pair of screen-relative character-cell coordinates are 875 enclosed by the given window, returning ``True`` or ``False``. It is useful for 876 determining what subset of the screen windows enclose the location of a mouse 877 event. 878 879 880.. attribute:: window.encoding 881 882 Encoding used to encode method arguments (Unicode strings and characters). 883 The encoding attribute is inherited from the parent window when a subwindow 884 is created, for example with :meth:`window.subwin`. By default, the locale 885 encoding is used (see :func:`locale.getpreferredencoding`). 886 887 .. versionadded:: 3.3 888 889 890.. method:: window.erase() 891 892 Clear the window. 893 894 895.. method:: window.getbegyx() 896 897 Return a tuple ``(y, x)`` of co-ordinates of upper-left corner. 898 899 900.. method:: window.getbkgd() 901 902 Return the given window's current background character/attribute pair. 903 904 905.. method:: window.getch([y, x]) 906 907 Get a character. Note that the integer returned does *not* have to be in ASCII 908 range: function keys, keypad keys and so on are represented by numbers higher 909 than 255. In no-delay mode, return ``-1`` if there is no input, otherwise 910 wait until a key is pressed. 911 912 913.. method:: window.get_wch([y, x]) 914 915 Get a wide character. Return a character for most keys, or an integer for 916 function keys, keypad keys, and other special keys. 917 In no-delay mode, raise an exception if there is no input. 918 919 .. versionadded:: 3.3 920 921 922.. method:: window.getkey([y, x]) 923 924 Get a character, returning a string instead of an integer, as :meth:`getch` 925 does. Function keys, keypad keys and other special keys return a multibyte 926 string containing the key name. In no-delay mode, raise an exception if 927 there is no input. 928 929 930.. method:: window.getmaxyx() 931 932 Return a tuple ``(y, x)`` of the height and width of the window. 933 934 935.. method:: window.getparyx() 936 937 Return the beginning coordinates of this window relative to its parent window 938 as a tuple ``(y, x)``. Return ``(-1, -1)`` if this window has no 939 parent. 940 941 942.. method:: window.getstr() 943 window.getstr(n) 944 window.getstr(y, x) 945 window.getstr(y, x, n) 946 947 Read a bytes object from the user, with primitive line editing capacity. 948 949 950.. method:: window.getyx() 951 952 Return a tuple ``(y, x)`` of current cursor position relative to the window's 953 upper-left corner. 954 955 956.. method:: window.hline(ch, n) 957 window.hline(y, x, ch, n) 958 959 Display a horizontal line starting at ``(y, x)`` with length *n* consisting of 960 the character *ch*. 961 962 963.. method:: window.idcok(flag) 964 965 If *flag* is ``False``, curses no longer considers using the hardware insert/delete 966 character feature of the terminal; if *flag* is ``True``, use of character insertion 967 and deletion is enabled. When curses is first initialized, use of character 968 insert/delete is enabled by default. 969 970 971.. method:: window.idlok(flag) 972 973 If *flag* is ``True``, :mod:`curses` will try and use hardware line 974 editing facilities. Otherwise, line insertion/deletion are disabled. 975 976 977.. method:: window.immedok(flag) 978 979 If *flag* is ``True``, any change in the window image automatically causes the 980 window to be refreshed; you no longer have to call :meth:`refresh` yourself. 981 However, it may degrade performance considerably, due to repeated calls to 982 wrefresh. This option is disabled by default. 983 984 985.. method:: window.inch([y, x]) 986 987 Return the character at the given position in the window. The bottom 8 bits are 988 the character proper, and upper bits are the attributes. 989 990 991.. method:: window.insch(ch[, attr]) 992 window.insch(y, x, ch[, attr]) 993 994 Paint character *ch* at ``(y, x)`` with attributes *attr*, moving the line from 995 position *x* right by one character. 996 997 998.. method:: window.insdelln(nlines) 999 1000 Insert *nlines* lines into the specified window above the current line. The 1001 *nlines* bottom lines are lost. For negative *nlines*, delete *nlines* lines 1002 starting with the one under the cursor, and move the remaining lines up. The 1003 bottom *nlines* lines are cleared. The current cursor position remains the 1004 same. 1005 1006 1007.. method:: window.insertln() 1008 1009 Insert a blank line under the cursor. All following lines are moved down by one 1010 line. 1011 1012 1013.. method:: window.insnstr(str, n[, attr]) 1014 window.insnstr(y, x, str, n[, attr]) 1015 1016 Insert a character string (as many characters as will fit on the line) before 1017 the character under the cursor, up to *n* characters. If *n* is zero or 1018 negative, the entire string is inserted. All characters to the right of the 1019 cursor are shifted right, with the rightmost characters on the line being lost. 1020 The cursor position does not change (after moving to *y*, *x*, if specified). 1021 1022 1023.. method:: window.insstr(str[, attr]) 1024 window.insstr(y, x, str[, attr]) 1025 1026 Insert a character string (as many characters as will fit on the line) before 1027 the character under the cursor. All characters to the right of the cursor are 1028 shifted right, with the rightmost characters on the line being lost. The cursor 1029 position does not change (after moving to *y*, *x*, if specified). 1030 1031 1032.. method:: window.instr([n]) 1033 window.instr(y, x[, n]) 1034 1035 Return a bytes object of characters, extracted from the window starting at the 1036 current cursor position, or at *y*, *x* if specified. Attributes are stripped 1037 from the characters. If *n* is specified, :meth:`instr` returns a string 1038 at most *n* characters long (exclusive of the trailing NUL). 1039 1040 1041.. method:: window.is_linetouched(line) 1042 1043 Return ``True`` if the specified line was modified since the last call to 1044 :meth:`refresh`; otherwise return ``False``. Raise a :exc:`curses.error` 1045 exception if *line* is not valid for the given window. 1046 1047 1048.. method:: window.is_wintouched() 1049 1050 Return ``True`` if the specified window was modified since the last call to 1051 :meth:`refresh`; otherwise return ``False``. 1052 1053 1054.. method:: window.keypad(flag) 1055 1056 If *flag* is ``True``, escape sequences generated by some keys (keypad, function keys) 1057 will be interpreted by :mod:`curses`. If *flag* is ``False``, escape sequences will be 1058 left as is in the input stream. 1059 1060 1061.. method:: window.leaveok(flag) 1062 1063 If *flag* is ``True``, cursor is left where it is on update, instead of being at "cursor 1064 position." This reduces cursor movement where possible. If possible the cursor 1065 will be made invisible. 1066 1067 If *flag* is ``False``, cursor will always be at "cursor position" after an update. 1068 1069 1070.. method:: window.move(new_y, new_x) 1071 1072 Move cursor to ``(new_y, new_x)``. 1073 1074 1075.. method:: window.mvderwin(y, x) 1076 1077 Move the window inside its parent window. The screen-relative parameters of 1078 the window are not changed. This routine is used to display different parts of 1079 the parent window at the same physical position on the screen. 1080 1081 1082.. method:: window.mvwin(new_y, new_x) 1083 1084 Move the window so its upper-left corner is at ``(new_y, new_x)``. 1085 1086 1087.. method:: window.nodelay(flag) 1088 1089 If *flag* is ``True``, :meth:`getch` will be non-blocking. 1090 1091 1092.. method:: window.notimeout(flag) 1093 1094 If *flag* is ``True``, escape sequences will not be timed out. 1095 1096 If *flag* is ``False``, after a few milliseconds, an escape sequence will not be 1097 interpreted, and will be left in the input stream as is. 1098 1099 1100.. method:: window.noutrefresh() 1101 1102 Mark for refresh but wait. This function updates the data structure 1103 representing the desired state of the window, but does not force an update of 1104 the physical screen. To accomplish that, call :func:`doupdate`. 1105 1106 1107.. method:: window.overlay(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol]) 1108 1109 Overlay the window on top of *destwin*. The windows need not be the same size, 1110 only the overlapping region is copied. This copy is non-destructive, which means 1111 that the current background character does not overwrite the old contents of 1112 *destwin*. 1113 1114 To get fine-grained control over the copied region, the second form of 1115 :meth:`overlay` can be used. *sminrow* and *smincol* are the upper-left 1116 coordinates of the source window, and the other variables mark a rectangle in 1117 the destination window. 1118 1119 1120.. method:: window.overwrite(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol]) 1121 1122 Overwrite the window on top of *destwin*. The windows need not be the same size, 1123 in which case only the overlapping region is copied. This copy is destructive, 1124 which means that the current background character overwrites the old contents of 1125 *destwin*. 1126 1127 To get fine-grained control over the copied region, the second form of 1128 :meth:`overwrite` can be used. *sminrow* and *smincol* are the upper-left 1129 coordinates of the source window, the other variables mark a rectangle in the 1130 destination window. 1131 1132 1133.. method:: window.putwin(file) 1134 1135 Write all data associated with the window into the provided file object. This 1136 information can be later retrieved using the :func:`getwin` function. 1137 1138 1139.. method:: window.redrawln(beg, num) 1140 1141 Indicate that the *num* screen lines, starting at line *beg*, are corrupted and 1142 should be completely redrawn on the next :meth:`refresh` call. 1143 1144 1145.. method:: window.redrawwin() 1146 1147 Touch the entire window, causing it to be completely redrawn on the next 1148 :meth:`refresh` call. 1149 1150 1151.. method:: window.refresh([pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol]) 1152 1153 Update the display immediately (sync actual screen with previous 1154 drawing/deleting methods). 1155 1156 The 6 optional arguments can only be specified when the window is a pad created 1157 with :func:`newpad`. The additional parameters are needed to indicate what part 1158 of the pad and screen are involved. *pminrow* and *pmincol* specify the upper 1159 left-hand corner of the rectangle to be displayed in the pad. *sminrow*, 1160 *smincol*, *smaxrow*, and *smaxcol* specify the edges of the rectangle to be 1161 displayed on the screen. The lower right-hand corner of the rectangle to be 1162 displayed in the pad is calculated from the screen coordinates, since the 1163 rectangles must be the same size. Both rectangles must be entirely contained 1164 within their respective structures. Negative values of *pminrow*, *pmincol*, 1165 *sminrow*, or *smincol* are treated as if they were zero. 1166 1167 1168.. method:: window.resize(nlines, ncols) 1169 1170 Reallocate storage for a curses window to adjust its dimensions to the 1171 specified values. If either dimension is larger than the current values, the 1172 window's data is filled with blanks that have the current background 1173 rendition (as set by :meth:`bkgdset`) merged into them. 1174 1175 1176.. method:: window.scroll([lines=1]) 1177 1178 Scroll the screen or scrolling region upward by *lines* lines. 1179 1180 1181.. method:: window.scrollok(flag) 1182 1183 Control what happens when the cursor of a window is moved off the edge of the 1184 window or scrolling region, either as a result of a newline action on the bottom 1185 line, or typing the last character of the last line. If *flag* is ``False``, the 1186 cursor is left on the bottom line. If *flag* is ``True``, the window is scrolled up 1187 one line. Note that in order to get the physical scrolling effect on the 1188 terminal, it is also necessary to call :meth:`idlok`. 1189 1190 1191.. method:: window.setscrreg(top, bottom) 1192 1193 Set the scrolling region from line *top* to line *bottom*. All scrolling actions 1194 will take place in this region. 1195 1196 1197.. method:: window.standend() 1198 1199 Turn off the standout attribute. On some terminals this has the side effect of 1200 turning off all attributes. 1201 1202 1203.. method:: window.standout() 1204 1205 Turn on attribute *A_STANDOUT*. 1206 1207 1208.. method:: window.subpad(begin_y, begin_x) 1209 window.subpad(nlines, ncols, begin_y, begin_x) 1210 1211 Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and 1212 whose width/height is *ncols*/*nlines*. 1213 1214 1215.. method:: window.subwin(begin_y, begin_x) 1216 window.subwin(nlines, ncols, begin_y, begin_x) 1217 1218 Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and 1219 whose width/height is *ncols*/*nlines*. 1220 1221 By default, the sub-window will extend from the specified position to the lower 1222 right corner of the window. 1223 1224 1225.. method:: window.syncdown() 1226 1227 Touch each location in the window that has been touched in any of its ancestor 1228 windows. This routine is called by :meth:`refresh`, so it should almost never 1229 be necessary to call it manually. 1230 1231 1232.. method:: window.syncok(flag) 1233 1234 If *flag* is ``True``, then :meth:`syncup` is called automatically 1235 whenever there is a change in the window. 1236 1237 1238.. method:: window.syncup() 1239 1240 Touch all locations in ancestors of the window that have been changed in the 1241 window. 1242 1243 1244.. method:: window.timeout(delay) 1245 1246 Set blocking or non-blocking read behavior for the window. If *delay* is 1247 negative, blocking read is used (which will wait indefinitely for input). If 1248 *delay* is zero, then non-blocking read is used, and :meth:`getch` will 1249 return ``-1`` if no input is waiting. If *delay* is positive, then 1250 :meth:`getch` will block for *delay* milliseconds, and return ``-1`` if there is 1251 still no input at the end of that time. 1252 1253 1254.. method:: window.touchline(start, count[, changed]) 1255 1256 Pretend *count* lines have been changed, starting with line *start*. If 1257 *changed* is supplied, it specifies whether the affected lines are marked as 1258 having been changed (*changed*\ ``=True``) or unchanged (*changed*\ ``=False``). 1259 1260 1261.. method:: window.touchwin() 1262 1263 Pretend the whole window has been changed, for purposes of drawing 1264 optimizations. 1265 1266 1267.. method:: window.untouchwin() 1268 1269 Mark all lines in the window as unchanged since the last call to 1270 :meth:`refresh`. 1271 1272 1273.. method:: window.vline(ch, n) 1274 window.vline(y, x, ch, n) 1275 1276 Display a vertical line starting at ``(y, x)`` with length *n* consisting of the 1277 character *ch*. 1278 1279 1280Constants 1281--------- 1282 1283The :mod:`curses` module defines the following data members: 1284 1285 1286.. data:: ERR 1287 1288 Some curses routines that return an integer, such as :meth:`~window.getch`, return 1289 :const:`ERR` upon failure. 1290 1291 1292.. data:: OK 1293 1294 Some curses routines that return an integer, such as :func:`napms`, return 1295 :const:`OK` upon success. 1296 1297 1298.. data:: version 1299 1300 A bytes object representing the current version of the module. Also available as 1301 :const:`__version__`. 1302 1303 1304.. data:: ncurses_version 1305 1306 A named tuple containing the three components of the ncurses library 1307 version: *major*, *minor*, and *patch*. All values are integers. The 1308 components can also be accessed by name, so ``curses.ncurses_version[0]`` 1309 is equivalent to ``curses.ncurses_version.major`` and so on. 1310 1311 Availability: if the ncurses library is used. 1312 1313 .. versionadded:: 3.8 1314 1315 1316Some constants are available to specify character cell attributes. 1317The exact constants available are system dependent. 1318 1319+------------------+-------------------------------+ 1320| Attribute | Meaning | 1321+==================+===============================+ 1322| ``A_ALTCHARSET`` | Alternate character set mode | 1323+------------------+-------------------------------+ 1324| ``A_BLINK`` | Blink mode | 1325+------------------+-------------------------------+ 1326| ``A_BOLD`` | Bold mode | 1327+------------------+-------------------------------+ 1328| ``A_DIM`` | Dim mode | 1329+------------------+-------------------------------+ 1330| ``A_INVIS`` | Invisible or blank mode | 1331+------------------+-------------------------------+ 1332| ``A_ITALIC`` | Italic mode | 1333+------------------+-------------------------------+ 1334| ``A_NORMAL`` | Normal attribute | 1335+------------------+-------------------------------+ 1336| ``A_PROTECT`` | Protected mode | 1337+------------------+-------------------------------+ 1338| ``A_REVERSE`` | Reverse background and | 1339| | foreground colors | 1340+------------------+-------------------------------+ 1341| ``A_STANDOUT`` | Standout mode | 1342+------------------+-------------------------------+ 1343| ``A_UNDERLINE`` | Underline mode | 1344+------------------+-------------------------------+ 1345| ``A_HORIZONTAL`` | Horizontal highlight | 1346+------------------+-------------------------------+ 1347| ``A_LEFT`` | Left highlight | 1348+------------------+-------------------------------+ 1349| ``A_LOW`` | Low highlight | 1350+------------------+-------------------------------+ 1351| ``A_RIGHT`` | Right highlight | 1352+------------------+-------------------------------+ 1353| ``A_TOP`` | Top highlight | 1354+------------------+-------------------------------+ 1355| ``A_VERTICAL`` | Vertical highlight | 1356+------------------+-------------------------------+ 1357| ``A_CHARTEXT`` | Bit-mask to extract a | 1358| | character | 1359+------------------+-------------------------------+ 1360 1361.. versionadded:: 3.7 1362 ``A_ITALIC`` was added. 1363 1364Several constants are available to extract corresponding attributes returned 1365by some methods. 1366 1367+------------------+-------------------------------+ 1368| Bit-mask | Meaning | 1369+==================+===============================+ 1370| ``A_ATTRIBUTES`` | Bit-mask to extract | 1371| | attributes | 1372+------------------+-------------------------------+ 1373| ``A_CHARTEXT`` | Bit-mask to extract a | 1374| | character | 1375+------------------+-------------------------------+ 1376| ``A_COLOR`` | Bit-mask to extract | 1377| | color-pair field information | 1378+------------------+-------------------------------+ 1379 1380Keys are referred to by integer constants with names starting with ``KEY_``. 1381The exact keycaps available are system dependent. 1382 1383.. XXX this table is far too large! should it be alphabetized? 1384 1385+-------------------+--------------------------------------------+ 1386| Key constant | Key | 1387+===================+============================================+ 1388| ``KEY_MIN`` | Minimum key value | 1389+-------------------+--------------------------------------------+ 1390| ``KEY_BREAK`` | Break key (unreliable) | 1391+-------------------+--------------------------------------------+ 1392| ``KEY_DOWN`` | Down-arrow | 1393+-------------------+--------------------------------------------+ 1394| ``KEY_UP`` | Up-arrow | 1395+-------------------+--------------------------------------------+ 1396| ``KEY_LEFT`` | Left-arrow | 1397+-------------------+--------------------------------------------+ 1398| ``KEY_RIGHT`` | Right-arrow | 1399+-------------------+--------------------------------------------+ 1400| ``KEY_HOME`` | Home key (upward+left arrow) | 1401+-------------------+--------------------------------------------+ 1402| ``KEY_BACKSPACE`` | Backspace (unreliable) | 1403+-------------------+--------------------------------------------+ 1404| ``KEY_F0`` | Function keys. Up to 64 function keys are | 1405| | supported. | 1406+-------------------+--------------------------------------------+ 1407| ``KEY_Fn`` | Value of function key *n* | 1408+-------------------+--------------------------------------------+ 1409| ``KEY_DL`` | Delete line | 1410+-------------------+--------------------------------------------+ 1411| ``KEY_IL`` | Insert line | 1412+-------------------+--------------------------------------------+ 1413| ``KEY_DC`` | Delete character | 1414+-------------------+--------------------------------------------+ 1415| ``KEY_IC`` | Insert char or enter insert mode | 1416+-------------------+--------------------------------------------+ 1417| ``KEY_EIC`` | Exit insert char mode | 1418+-------------------+--------------------------------------------+ 1419| ``KEY_CLEAR`` | Clear screen | 1420+-------------------+--------------------------------------------+ 1421| ``KEY_EOS`` | Clear to end of screen | 1422+-------------------+--------------------------------------------+ 1423| ``KEY_EOL`` | Clear to end of line | 1424+-------------------+--------------------------------------------+ 1425| ``KEY_SF`` | Scroll 1 line forward | 1426+-------------------+--------------------------------------------+ 1427| ``KEY_SR`` | Scroll 1 line backward (reverse) | 1428+-------------------+--------------------------------------------+ 1429| ``KEY_NPAGE`` | Next page | 1430+-------------------+--------------------------------------------+ 1431| ``KEY_PPAGE`` | Previous page | 1432+-------------------+--------------------------------------------+ 1433| ``KEY_STAB`` | Set tab | 1434+-------------------+--------------------------------------------+ 1435| ``KEY_CTAB`` | Clear tab | 1436+-------------------+--------------------------------------------+ 1437| ``KEY_CATAB`` | Clear all tabs | 1438+-------------------+--------------------------------------------+ 1439| ``KEY_ENTER`` | Enter or send (unreliable) | 1440+-------------------+--------------------------------------------+ 1441| ``KEY_SRESET`` | Soft (partial) reset (unreliable) | 1442+-------------------+--------------------------------------------+ 1443| ``KEY_RESET`` | Reset or hard reset (unreliable) | 1444+-------------------+--------------------------------------------+ 1445| ``KEY_PRINT`` | Print | 1446+-------------------+--------------------------------------------+ 1447| ``KEY_LL`` | Home down or bottom (lower left) | 1448+-------------------+--------------------------------------------+ 1449| ``KEY_A1`` | Upper left of keypad | 1450+-------------------+--------------------------------------------+ 1451| ``KEY_A3`` | Upper right of keypad | 1452+-------------------+--------------------------------------------+ 1453| ``KEY_B2`` | Center of keypad | 1454+-------------------+--------------------------------------------+ 1455| ``KEY_C1`` | Lower left of keypad | 1456+-------------------+--------------------------------------------+ 1457| ``KEY_C3`` | Lower right of keypad | 1458+-------------------+--------------------------------------------+ 1459| ``KEY_BTAB`` | Back tab | 1460+-------------------+--------------------------------------------+ 1461| ``KEY_BEG`` | Beg (beginning) | 1462+-------------------+--------------------------------------------+ 1463| ``KEY_CANCEL`` | Cancel | 1464+-------------------+--------------------------------------------+ 1465| ``KEY_CLOSE`` | Close | 1466+-------------------+--------------------------------------------+ 1467| ``KEY_COMMAND`` | Cmd (command) | 1468+-------------------+--------------------------------------------+ 1469| ``KEY_COPY`` | Copy | 1470+-------------------+--------------------------------------------+ 1471| ``KEY_CREATE`` | Create | 1472+-------------------+--------------------------------------------+ 1473| ``KEY_END`` | End | 1474+-------------------+--------------------------------------------+ 1475| ``KEY_EXIT`` | Exit | 1476+-------------------+--------------------------------------------+ 1477| ``KEY_FIND`` | Find | 1478+-------------------+--------------------------------------------+ 1479| ``KEY_HELP`` | Help | 1480+-------------------+--------------------------------------------+ 1481| ``KEY_MARK`` | Mark | 1482+-------------------+--------------------------------------------+ 1483| ``KEY_MESSAGE`` | Message | 1484+-------------------+--------------------------------------------+ 1485| ``KEY_MOVE`` | Move | 1486+-------------------+--------------------------------------------+ 1487| ``KEY_NEXT`` | Next | 1488+-------------------+--------------------------------------------+ 1489| ``KEY_OPEN`` | Open | 1490+-------------------+--------------------------------------------+ 1491| ``KEY_OPTIONS`` | Options | 1492+-------------------+--------------------------------------------+ 1493| ``KEY_PREVIOUS`` | Prev (previous) | 1494+-------------------+--------------------------------------------+ 1495| ``KEY_REDO`` | Redo | 1496+-------------------+--------------------------------------------+ 1497| ``KEY_REFERENCE`` | Ref (reference) | 1498+-------------------+--------------------------------------------+ 1499| ``KEY_REFRESH`` | Refresh | 1500+-------------------+--------------------------------------------+ 1501| ``KEY_REPLACE`` | Replace | 1502+-------------------+--------------------------------------------+ 1503| ``KEY_RESTART`` | Restart | 1504+-------------------+--------------------------------------------+ 1505| ``KEY_RESUME`` | Resume | 1506+-------------------+--------------------------------------------+ 1507| ``KEY_SAVE`` | Save | 1508+-------------------+--------------------------------------------+ 1509| ``KEY_SBEG`` | Shifted Beg (beginning) | 1510+-------------------+--------------------------------------------+ 1511| ``KEY_SCANCEL`` | Shifted Cancel | 1512+-------------------+--------------------------------------------+ 1513| ``KEY_SCOMMAND`` | Shifted Command | 1514+-------------------+--------------------------------------------+ 1515| ``KEY_SCOPY`` | Shifted Copy | 1516+-------------------+--------------------------------------------+ 1517| ``KEY_SCREATE`` | Shifted Create | 1518+-------------------+--------------------------------------------+ 1519| ``KEY_SDC`` | Shifted Delete char | 1520+-------------------+--------------------------------------------+ 1521| ``KEY_SDL`` | Shifted Delete line | 1522+-------------------+--------------------------------------------+ 1523| ``KEY_SELECT`` | Select | 1524+-------------------+--------------------------------------------+ 1525| ``KEY_SEND`` | Shifted End | 1526+-------------------+--------------------------------------------+ 1527| ``KEY_SEOL`` | Shifted Clear line | 1528+-------------------+--------------------------------------------+ 1529| ``KEY_SEXIT`` | Shifted Exit | 1530+-------------------+--------------------------------------------+ 1531| ``KEY_SFIND`` | Shifted Find | 1532+-------------------+--------------------------------------------+ 1533| ``KEY_SHELP`` | Shifted Help | 1534+-------------------+--------------------------------------------+ 1535| ``KEY_SHOME`` | Shifted Home | 1536+-------------------+--------------------------------------------+ 1537| ``KEY_SIC`` | Shifted Input | 1538+-------------------+--------------------------------------------+ 1539| ``KEY_SLEFT`` | Shifted Left arrow | 1540+-------------------+--------------------------------------------+ 1541| ``KEY_SMESSAGE`` | Shifted Message | 1542+-------------------+--------------------------------------------+ 1543| ``KEY_SMOVE`` | Shifted Move | 1544+-------------------+--------------------------------------------+ 1545| ``KEY_SNEXT`` | Shifted Next | 1546+-------------------+--------------------------------------------+ 1547| ``KEY_SOPTIONS`` | Shifted Options | 1548+-------------------+--------------------------------------------+ 1549| ``KEY_SPREVIOUS`` | Shifted Prev | 1550+-------------------+--------------------------------------------+ 1551| ``KEY_SPRINT`` | Shifted Print | 1552+-------------------+--------------------------------------------+ 1553| ``KEY_SREDO`` | Shifted Redo | 1554+-------------------+--------------------------------------------+ 1555| ``KEY_SREPLACE`` | Shifted Replace | 1556+-------------------+--------------------------------------------+ 1557| ``KEY_SRIGHT`` | Shifted Right arrow | 1558+-------------------+--------------------------------------------+ 1559| ``KEY_SRSUME`` | Shifted Resume | 1560+-------------------+--------------------------------------------+ 1561| ``KEY_SSAVE`` | Shifted Save | 1562+-------------------+--------------------------------------------+ 1563| ``KEY_SSUSPEND`` | Shifted Suspend | 1564+-------------------+--------------------------------------------+ 1565| ``KEY_SUNDO`` | Shifted Undo | 1566+-------------------+--------------------------------------------+ 1567| ``KEY_SUSPEND`` | Suspend | 1568+-------------------+--------------------------------------------+ 1569| ``KEY_UNDO`` | Undo | 1570+-------------------+--------------------------------------------+ 1571| ``KEY_MOUSE`` | Mouse event has occurred | 1572+-------------------+--------------------------------------------+ 1573| ``KEY_RESIZE`` | Terminal resize event | 1574+-------------------+--------------------------------------------+ 1575| ``KEY_MAX`` | Maximum key value | 1576+-------------------+--------------------------------------------+ 1577 1578On VT100s and their software emulations, such as X terminal emulators, there are 1579normally at least four function keys (:const:`KEY_F1`, :const:`KEY_F2`, 1580:const:`KEY_F3`, :const:`KEY_F4`) available, and the arrow keys mapped to 1581:const:`KEY_UP`, :const:`KEY_DOWN`, :const:`KEY_LEFT` and :const:`KEY_RIGHT` in 1582the obvious way. If your machine has a PC keyboard, it is safe to expect arrow 1583keys and twelve function keys (older PC keyboards may have only ten function 1584keys); also, the following keypad mappings are standard: 1585 1586+------------------+-----------+ 1587| Keycap | Constant | 1588+==================+===========+ 1589| :kbd:`Insert` | KEY_IC | 1590+------------------+-----------+ 1591| :kbd:`Delete` | KEY_DC | 1592+------------------+-----------+ 1593| :kbd:`Home` | KEY_HOME | 1594+------------------+-----------+ 1595| :kbd:`End` | KEY_END | 1596+------------------+-----------+ 1597| :kbd:`Page Up` | KEY_PPAGE | 1598+------------------+-----------+ 1599| :kbd:`Page Down` | KEY_NPAGE | 1600+------------------+-----------+ 1601 1602The following table lists characters from the alternate character set. These are 1603inherited from the VT100 terminal, and will generally be available on software 1604emulations such as X terminals. When there is no graphic available, curses 1605falls back on a crude printable ASCII approximation. 1606 1607.. note:: 1608 1609 These are available only after :func:`initscr` has been called. 1610 1611+------------------+------------------------------------------+ 1612| ACS code | Meaning | 1613+==================+==========================================+ 1614| ``ACS_BBSS`` | alternate name for upper right corner | 1615+------------------+------------------------------------------+ 1616| ``ACS_BLOCK`` | solid square block | 1617+------------------+------------------------------------------+ 1618| ``ACS_BOARD`` | board of squares | 1619+------------------+------------------------------------------+ 1620| ``ACS_BSBS`` | alternate name for horizontal line | 1621+------------------+------------------------------------------+ 1622| ``ACS_BSSB`` | alternate name for upper left corner | 1623+------------------+------------------------------------------+ 1624| ``ACS_BSSS`` | alternate name for top tee | 1625+------------------+------------------------------------------+ 1626| ``ACS_BTEE`` | bottom tee | 1627+------------------+------------------------------------------+ 1628| ``ACS_BULLET`` | bullet | 1629+------------------+------------------------------------------+ 1630| ``ACS_CKBOARD`` | checker board (stipple) | 1631+------------------+------------------------------------------+ 1632| ``ACS_DARROW`` | arrow pointing down | 1633+------------------+------------------------------------------+ 1634| ``ACS_DEGREE`` | degree symbol | 1635+------------------+------------------------------------------+ 1636| ``ACS_DIAMOND`` | diamond | 1637+------------------+------------------------------------------+ 1638| ``ACS_GEQUAL`` | greater-than-or-equal-to | 1639+------------------+------------------------------------------+ 1640| ``ACS_HLINE`` | horizontal line | 1641+------------------+------------------------------------------+ 1642| ``ACS_LANTERN`` | lantern symbol | 1643+------------------+------------------------------------------+ 1644| ``ACS_LARROW`` | left arrow | 1645+------------------+------------------------------------------+ 1646| ``ACS_LEQUAL`` | less-than-or-equal-to | 1647+------------------+------------------------------------------+ 1648| ``ACS_LLCORNER`` | lower left-hand corner | 1649+------------------+------------------------------------------+ 1650| ``ACS_LRCORNER`` | lower right-hand corner | 1651+------------------+------------------------------------------+ 1652| ``ACS_LTEE`` | left tee | 1653+------------------+------------------------------------------+ 1654| ``ACS_NEQUAL`` | not-equal sign | 1655+------------------+------------------------------------------+ 1656| ``ACS_PI`` | letter pi | 1657+------------------+------------------------------------------+ 1658| ``ACS_PLMINUS`` | plus-or-minus sign | 1659+------------------+------------------------------------------+ 1660| ``ACS_PLUS`` | big plus sign | 1661+------------------+------------------------------------------+ 1662| ``ACS_RARROW`` | right arrow | 1663+------------------+------------------------------------------+ 1664| ``ACS_RTEE`` | right tee | 1665+------------------+------------------------------------------+ 1666| ``ACS_S1`` | scan line 1 | 1667+------------------+------------------------------------------+ 1668| ``ACS_S3`` | scan line 3 | 1669+------------------+------------------------------------------+ 1670| ``ACS_S7`` | scan line 7 | 1671+------------------+------------------------------------------+ 1672| ``ACS_S9`` | scan line 9 | 1673+------------------+------------------------------------------+ 1674| ``ACS_SBBS`` | alternate name for lower right corner | 1675+------------------+------------------------------------------+ 1676| ``ACS_SBSB`` | alternate name for vertical line | 1677+------------------+------------------------------------------+ 1678| ``ACS_SBSS`` | alternate name for right tee | 1679+------------------+------------------------------------------+ 1680| ``ACS_SSBB`` | alternate name for lower left corner | 1681+------------------+------------------------------------------+ 1682| ``ACS_SSBS`` | alternate name for bottom tee | 1683+------------------+------------------------------------------+ 1684| ``ACS_SSSB`` | alternate name for left tee | 1685+------------------+------------------------------------------+ 1686| ``ACS_SSSS`` | alternate name for crossover or big plus | 1687+------------------+------------------------------------------+ 1688| ``ACS_STERLING`` | pound sterling | 1689+------------------+------------------------------------------+ 1690| ``ACS_TTEE`` | top tee | 1691+------------------+------------------------------------------+ 1692| ``ACS_UARROW`` | up arrow | 1693+------------------+------------------------------------------+ 1694| ``ACS_ULCORNER`` | upper left corner | 1695+------------------+------------------------------------------+ 1696| ``ACS_URCORNER`` | upper right corner | 1697+------------------+------------------------------------------+ 1698| ``ACS_VLINE`` | vertical line | 1699+------------------+------------------------------------------+ 1700 1701The following table lists the predefined colors: 1702 1703+-------------------+----------------------------+ 1704| Constant | Color | 1705+===================+============================+ 1706| ``COLOR_BLACK`` | Black | 1707+-------------------+----------------------------+ 1708| ``COLOR_BLUE`` | Blue | 1709+-------------------+----------------------------+ 1710| ``COLOR_CYAN`` | Cyan (light greenish blue) | 1711+-------------------+----------------------------+ 1712| ``COLOR_GREEN`` | Green | 1713+-------------------+----------------------------+ 1714| ``COLOR_MAGENTA`` | Magenta (purplish red) | 1715+-------------------+----------------------------+ 1716| ``COLOR_RED`` | Red | 1717+-------------------+----------------------------+ 1718| ``COLOR_WHITE`` | White | 1719+-------------------+----------------------------+ 1720| ``COLOR_YELLOW`` | Yellow | 1721+-------------------+----------------------------+ 1722 1723 1724:mod:`curses.textpad` --- Text input widget for curses programs 1725=============================================================== 1726 1727.. module:: curses.textpad 1728 :synopsis: Emacs-like input editing in a curses window. 1729.. moduleauthor:: Eric Raymond <esr@thyrsus.com> 1730.. sectionauthor:: Eric Raymond <esr@thyrsus.com> 1731 1732 1733The :mod:`curses.textpad` module provides a :class:`Textbox` class that handles 1734elementary text editing in a curses window, supporting a set of keybindings 1735resembling those of Emacs (thus, also of Netscape Navigator, BBedit 6.x, 1736FrameMaker, and many other programs). The module also provides a 1737rectangle-drawing function useful for framing text boxes or for other purposes. 1738 1739The module :mod:`curses.textpad` defines the following function: 1740 1741 1742.. function:: rectangle(win, uly, ulx, lry, lrx) 1743 1744 Draw a rectangle. The first argument must be a window object; the remaining 1745 arguments are coordinates relative to that window. The second and third 1746 arguments are the y and x coordinates of the upper left hand corner of the 1747 rectangle to be drawn; the fourth and fifth arguments are the y and x 1748 coordinates of the lower right hand corner. The rectangle will be drawn using 1749 VT100/IBM PC forms characters on terminals that make this possible (including 1750 xterm and most other software terminal emulators). Otherwise it will be drawn 1751 with ASCII dashes, vertical bars, and plus signs. 1752 1753 1754.. _curses-textpad-objects: 1755 1756Textbox objects 1757--------------- 1758 1759You can instantiate a :class:`Textbox` object as follows: 1760 1761 1762.. class:: Textbox(win) 1763 1764 Return a textbox widget object. The *win* argument should be a curses 1765 :ref:`window <curses-window-objects>` object in which the textbox is to 1766 be contained. The edit cursor of the textbox is initially located at the 1767 upper left hand corner of the containing window, with coordinates ``(0, 0)``. 1768 The instance's :attr:`stripspaces` flag is initially on. 1769 1770 :class:`Textbox` objects have the following methods: 1771 1772 1773 .. method:: edit([validator]) 1774 1775 This is the entry point you will normally use. It accepts editing 1776 keystrokes until one of the termination keystrokes is entered. If 1777 *validator* is supplied, it must be a function. It will be called for 1778 each keystroke entered with the keystroke as a parameter; command dispatch 1779 is done on the result. This method returns the window contents as a 1780 string; whether blanks in the window are included is affected by the 1781 :attr:`stripspaces` attribute. 1782 1783 1784 .. method:: do_command(ch) 1785 1786 Process a single command keystroke. Here are the supported special 1787 keystrokes: 1788 1789 +------------------+-------------------------------------------+ 1790 | Keystroke | Action | 1791 +==================+===========================================+ 1792 | :kbd:`Control-A` | Go to left edge of window. | 1793 +------------------+-------------------------------------------+ 1794 | :kbd:`Control-B` | Cursor left, wrapping to previous line if | 1795 | | appropriate. | 1796 +------------------+-------------------------------------------+ 1797 | :kbd:`Control-D` | Delete character under cursor. | 1798 +------------------+-------------------------------------------+ 1799 | :kbd:`Control-E` | Go to right edge (stripspaces off) or end | 1800 | | of line (stripspaces on). | 1801 +------------------+-------------------------------------------+ 1802 | :kbd:`Control-F` | Cursor right, wrapping to next line when | 1803 | | appropriate. | 1804 +------------------+-------------------------------------------+ 1805 | :kbd:`Control-G` | Terminate, returning the window contents. | 1806 +------------------+-------------------------------------------+ 1807 | :kbd:`Control-H` | Delete character backward. | 1808 +------------------+-------------------------------------------+ 1809 | :kbd:`Control-J` | Terminate if the window is 1 line, | 1810 | | otherwise insert newline. | 1811 +------------------+-------------------------------------------+ 1812 | :kbd:`Control-K` | If line is blank, delete it, otherwise | 1813 | | clear to end of line. | 1814 +------------------+-------------------------------------------+ 1815 | :kbd:`Control-L` | Refresh screen. | 1816 +------------------+-------------------------------------------+ 1817 | :kbd:`Control-N` | Cursor down; move down one line. | 1818 +------------------+-------------------------------------------+ 1819 | :kbd:`Control-O` | Insert a blank line at cursor location. | 1820 +------------------+-------------------------------------------+ 1821 | :kbd:`Control-P` | Cursor up; move up one line. | 1822 +------------------+-------------------------------------------+ 1823 1824 Move operations do nothing if the cursor is at an edge where the movement 1825 is not possible. The following synonyms are supported where possible: 1826 1827 +------------------------+------------------+ 1828 | Constant | Keystroke | 1829 +========================+==================+ 1830 | :const:`KEY_LEFT` | :kbd:`Control-B` | 1831 +------------------------+------------------+ 1832 | :const:`KEY_RIGHT` | :kbd:`Control-F` | 1833 +------------------------+------------------+ 1834 | :const:`KEY_UP` | :kbd:`Control-P` | 1835 +------------------------+------------------+ 1836 | :const:`KEY_DOWN` | :kbd:`Control-N` | 1837 +------------------------+------------------+ 1838 | :const:`KEY_BACKSPACE` | :kbd:`Control-h` | 1839 +------------------------+------------------+ 1840 1841 All other keystrokes are treated as a command to insert the given 1842 character and move right (with line wrapping). 1843 1844 1845 .. method:: gather() 1846 1847 Return the window contents as a string; whether blanks in the 1848 window are included is affected by the :attr:`stripspaces` member. 1849 1850 1851 .. attribute:: stripspaces 1852 1853 This attribute is a flag which controls the interpretation of blanks in 1854 the window. When it is on, trailing blanks on each line are ignored; any 1855 cursor motion that would land the cursor on a trailing blank goes to the 1856 end of that line instead, and trailing blanks are stripped when the window 1857 contents are gathered. 1858