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.. function:: get_escdelay() 517 518 Retrieves the value set by :func:`set_escdelay`. 519 520 .. versionadded:: 3.9 521 522.. function:: set_escdelay(ms) 523 524 Sets the number of milliseconds to wait after reading an escape character, 525 to distinguish between an individual escape character entered on the 526 keyboard from escape sequences sent by cursor and function keys. 527 528 .. versionadded:: 3.9 529 530.. function:: get_tabsize() 531 532 Retrieves the value set by :func:`set_tabsize`. 533 534 .. versionadded:: 3.9 535 536.. function:: set_tabsize(size) 537 538 Sets the number of columns used by the curses library when converting a tab 539 character to spaces as it adds the tab to a window. 540 541 .. versionadded:: 3.9 542 543.. function:: setsyx(y, x) 544 545 Set the virtual screen cursor to *y*, *x*. If *y* and *x* are both ``-1``, then 546 :meth:`leaveok <window.leaveok>` is set ``True``. 547 548 549.. function:: setupterm(term=None, fd=-1) 550 551 Initialize the terminal. *term* is a string giving 552 the terminal name, or ``None``; if omitted or ``None``, the value of the 553 :envvar:`TERM` environment variable will be used. *fd* is the 554 file descriptor to which any initialization sequences will be sent; if not 555 supplied or ``-1``, the file descriptor for ``sys.stdout`` will be used. 556 557 558.. function:: start_color() 559 560 Must be called if the programmer wants to use colors, and before any other color 561 manipulation routine is called. It is good practice to call this routine right 562 after :func:`initscr`. 563 564 :func:`start_color` initializes eight basic colors (black, red, green, yellow, 565 blue, magenta, cyan, and white), and two global variables in the :mod:`curses` 566 module, :const:`COLORS` and :const:`COLOR_PAIRS`, containing the maximum number 567 of colors and color-pairs the terminal can support. It also restores the colors 568 on the terminal to the values they had when the terminal was just turned on. 569 570 571.. function:: termattrs() 572 573 Return a logical OR of all video attributes supported by the terminal. This 574 information is useful when a curses program needs complete control over the 575 appearance of the screen. 576 577 578.. function:: termname() 579 580 Return the value of the environment variable :envvar:`TERM`, as a bytes object, 581 truncated to 14 characters. 582 583 584.. function:: tigetflag(capname) 585 586 Return the value of the Boolean capability corresponding to the terminfo 587 capability name *capname* as an integer. Return the value ``-1`` if *capname* is not a 588 Boolean capability, or ``0`` if it is canceled or absent from the terminal 589 description. 590 591 592.. function:: tigetnum(capname) 593 594 Return the value of the numeric capability corresponding to the terminfo 595 capability name *capname* as an integer. Return the value ``-2`` if *capname* is not a 596 numeric capability, or ``-1`` if it is canceled or absent from the terminal 597 description. 598 599 600.. function:: tigetstr(capname) 601 602 Return the value of the string capability corresponding to the terminfo 603 capability name *capname* as a bytes object. Return ``None`` if *capname* 604 is not a terminfo "string capability", or is canceled or absent from the 605 terminal description. 606 607 608.. function:: tparm(str[, ...]) 609 610 Instantiate the bytes object *str* with the supplied parameters, where *str* should 611 be a parameterized string obtained from the terminfo database. E.g. 612 ``tparm(tigetstr("cup"), 5, 3)`` could result in ``b'\033[6;4H'``, the exact 613 result depending on terminal type. 614 615 616.. function:: typeahead(fd) 617 618 Specify that the file descriptor *fd* be used for typeahead checking. If *fd* 619 is ``-1``, then no typeahead checking is done. 620 621 The curses library does "line-breakout optimization" by looking for typeahead 622 periodically while updating the screen. If input is found, and it is coming 623 from a tty, the current update is postponed until refresh or doupdate is called 624 again, allowing faster response to commands typed in advance. This function 625 allows specifying a different file descriptor for typeahead checking. 626 627 628.. function:: unctrl(ch) 629 630 Return a bytes object which is a printable representation of the character *ch*. 631 Control characters are represented as a caret followed by the character, for 632 example as ``b'^C'``. Printing characters are left as they are. 633 634 635.. function:: ungetch(ch) 636 637 Push *ch* so the next :meth:`~window.getch` will return it. 638 639 .. note:: 640 641 Only one *ch* can be pushed before :meth:`!getch` is called. 642 643 644.. function:: update_lines_cols() 645 646 Update :envvar:`LINES` and :envvar:`COLS`. Useful for detecting manual screen resize. 647 648 .. versionadded:: 3.5 649 650 651.. function:: unget_wch(ch) 652 653 Push *ch* so the next :meth:`~window.get_wch` will return it. 654 655 .. note:: 656 657 Only one *ch* can be pushed before :meth:`!get_wch` is called. 658 659 .. versionadded:: 3.3 660 661 662.. function:: ungetmouse(id, x, y, z, bstate) 663 664 Push a :const:`KEY_MOUSE` event onto the input queue, associating the given 665 state data with it. 666 667 668.. function:: use_env(flag) 669 670 If used, this function should be called before :func:`initscr` or newterm are 671 called. When *flag* is ``False``, the values of lines and columns specified in the 672 terminfo database will be used, even if environment variables :envvar:`LINES` 673 and :envvar:`COLUMNS` (used by default) are set, or if curses is running in a 674 window (in which case default behavior would be to use the window size if 675 :envvar:`LINES` and :envvar:`COLUMNS` are not set). 676 677 678.. function:: use_default_colors() 679 680 Allow use of default values for colors on terminals supporting this feature. Use 681 this to support transparency in your application. The default color is assigned 682 to the color number ``-1``. After calling this function, ``init_pair(x, 683 curses.COLOR_RED, -1)`` initializes, for instance, color pair *x* to a red 684 foreground color on the default background. 685 686 687.. function:: wrapper(func, /, *args, **kwargs) 688 689 Initialize curses and call another callable object, *func*, which should be the 690 rest of your curses-using application. If the application raises an exception, 691 this function will restore the terminal to a sane state before re-raising the 692 exception and generating a traceback. The callable object *func* is then passed 693 the main window 'stdscr' as its first argument, followed by any other arguments 694 passed to :func:`!wrapper`. Before calling *func*, :func:`!wrapper` turns on 695 cbreak mode, turns off echo, enables the terminal keypad, and initializes colors 696 if the terminal has color support. On exit (whether normally or by exception) 697 it restores cooked mode, turns on echo, and disables the terminal keypad. 698 699 700.. _curses-window-objects: 701 702Window Objects 703-------------- 704 705Window objects, as returned by :func:`initscr` and :func:`newwin` above, have 706the following methods and attributes: 707 708 709.. method:: window.addch(ch[, attr]) 710 window.addch(y, x, ch[, attr]) 711 712 Paint character *ch* at ``(y, x)`` with attributes *attr*, overwriting any 713 character previously painted at that location. By default, the character 714 position and attributes are the current settings for the window object. 715 716 .. note:: 717 718 Writing outside the window, subwindow, or pad raises a :exc:`curses.error`. 719 Attempting to write to the lower right corner of a window, subwindow, 720 or pad will cause an exception to be raised after the character is printed. 721 722 723.. method:: window.addnstr(str, n[, attr]) 724 window.addnstr(y, x, str, n[, attr]) 725 726 Paint at most *n* characters of the character string *str* at 727 ``(y, x)`` with attributes 728 *attr*, overwriting anything previously on the display. 729 730 731.. method:: window.addstr(str[, attr]) 732 window.addstr(y, x, str[, attr]) 733 734 Paint the character string *str* at ``(y, x)`` with attributes 735 *attr*, overwriting anything previously on the display. 736 737 .. note:: 738 739 * Writing outside the window, subwindow, or pad raises :exc:`curses.error`. 740 Attempting to write to the lower right corner of a window, subwindow, 741 or pad will cause an exception to be raised after the string is printed. 742 743 * A `bug in ncurses <https://bugs.python.org/issue35924>`_, the backend 744 for this Python module, can cause SegFaults when resizing windows. This 745 is fixed in ncurses-6.1-20190511. If you are stuck with an earlier 746 ncurses, you can avoid triggering this if you do not call :func:`addstr` 747 with a *str* that has embedded newlines. Instead, call :func:`addstr` 748 separately for each line. 749 750 751.. method:: window.attroff(attr) 752 753 Remove attribute *attr* from the "background" set applied to all writes to the 754 current window. 755 756 757.. method:: window.attron(attr) 758 759 Add attribute *attr* from the "background" set applied to all writes to the 760 current window. 761 762 763.. method:: window.attrset(attr) 764 765 Set the "background" set of attributes to *attr*. This set is initially 766 ``0`` (no attributes). 767 768 769.. method:: window.bkgd(ch[, attr]) 770 771 Set the background property of the window to the character *ch*, with 772 attributes *attr*. The change is then applied to every character position in 773 that window: 774 775 * The attribute of every character in the window is changed to the new 776 background attribute. 777 778 * Wherever the former background character appears, it is changed to the new 779 background character. 780 781 782.. method:: window.bkgdset(ch[, attr]) 783 784 Set the window's background. A window's background consists of a character and 785 any combination of attributes. The attribute part of the background is combined 786 (OR'ed) with all non-blank characters that are written into the window. Both 787 the character and attribute parts of the background are combined with the blank 788 characters. The background becomes a property of the character and moves with 789 the character through any scrolling and insert/delete line/character operations. 790 791 792.. method:: window.border([ls[, rs[, ts[, bs[, tl[, tr[, bl[, br]]]]]]]]) 793 794 Draw a border around the edges of the window. Each parameter specifies the 795 character to use for a specific part of the border; see the table below for more 796 details. 797 798 .. note:: 799 800 A ``0`` value for any parameter will cause the default character to be used for 801 that parameter. Keyword parameters can *not* be used. The defaults are listed 802 in this table: 803 804 +-----------+---------------------+-----------------------+ 805 | Parameter | Description | Default value | 806 +===========+=====================+=======================+ 807 | *ls* | Left side | :const:`ACS_VLINE` | 808 +-----------+---------------------+-----------------------+ 809 | *rs* | Right side | :const:`ACS_VLINE` | 810 +-----------+---------------------+-----------------------+ 811 | *ts* | Top | :const:`ACS_HLINE` | 812 +-----------+---------------------+-----------------------+ 813 | *bs* | Bottom | :const:`ACS_HLINE` | 814 +-----------+---------------------+-----------------------+ 815 | *tl* | Upper-left corner | :const:`ACS_ULCORNER` | 816 +-----------+---------------------+-----------------------+ 817 | *tr* | Upper-right corner | :const:`ACS_URCORNER` | 818 +-----------+---------------------+-----------------------+ 819 | *bl* | Bottom-left corner | :const:`ACS_LLCORNER` | 820 +-----------+---------------------+-----------------------+ 821 | *br* | Bottom-right corner | :const:`ACS_LRCORNER` | 822 +-----------+---------------------+-----------------------+ 823 824 825.. method:: window.box([vertch, horch]) 826 827 Similar to :meth:`border`, but both *ls* and *rs* are *vertch* and both *ts* and 828 *bs* are *horch*. The default corner characters are always used by this function. 829 830 831.. method:: window.chgat(attr) 832 window.chgat(num, attr) 833 window.chgat(y, x, attr) 834 window.chgat(y, x, num, attr) 835 836 Set the attributes of *num* characters at the current cursor position, or at 837 position ``(y, x)`` if supplied. If *num* is not given or is ``-1``, 838 the attribute will be set on all the characters to the end of the line. This 839 function moves cursor to position ``(y, x)`` if supplied. The changed line 840 will be touched using the :meth:`touchline` method so that the contents will 841 be redisplayed by the next window refresh. 842 843 844.. method:: window.clear() 845 846 Like :meth:`erase`, but also cause the whole window to be repainted upon next 847 call to :meth:`refresh`. 848 849 850.. method:: window.clearok(flag) 851 852 If *flag* is ``True``, the next call to :meth:`refresh` will clear the window 853 completely. 854 855 856.. method:: window.clrtobot() 857 858 Erase from cursor to the end of the window: all lines below the cursor are 859 deleted, and then the equivalent of :meth:`clrtoeol` is performed. 860 861 862.. method:: window.clrtoeol() 863 864 Erase from cursor to the end of the line. 865 866 867.. method:: window.cursyncup() 868 869 Update the current cursor position of all the ancestors of the window to 870 reflect the current cursor position of the window. 871 872 873.. method:: window.delch([y, x]) 874 875 Delete any character at ``(y, x)``. 876 877 878.. method:: window.deleteln() 879 880 Delete the line under the cursor. All following lines are moved up by one line. 881 882 883.. method:: window.derwin(begin_y, begin_x) 884 window.derwin(nlines, ncols, begin_y, begin_x) 885 886 An abbreviation for "derive window", :meth:`derwin` is the same as calling 887 :meth:`subwin`, except that *begin_y* and *begin_x* are relative to the origin 888 of the window, rather than relative to the entire screen. Return a window 889 object for the derived window. 890 891 892.. method:: window.echochar(ch[, attr]) 893 894 Add character *ch* with attribute *attr*, and immediately call :meth:`refresh` 895 on the window. 896 897 898.. method:: window.enclose(y, x) 899 900 Test whether the given pair of screen-relative character-cell coordinates are 901 enclosed by the given window, returning ``True`` or ``False``. It is useful for 902 determining what subset of the screen windows enclose the location of a mouse 903 event. 904 905 906.. attribute:: window.encoding 907 908 Encoding used to encode method arguments (Unicode strings and characters). 909 The encoding attribute is inherited from the parent window when a subwindow 910 is created, for example with :meth:`window.subwin`. By default, the locale 911 encoding is used (see :func:`locale.getpreferredencoding`). 912 913 .. versionadded:: 3.3 914 915 916.. method:: window.erase() 917 918 Clear the window. 919 920 921.. method:: window.getbegyx() 922 923 Return a tuple ``(y, x)`` of co-ordinates of upper-left corner. 924 925 926.. method:: window.getbkgd() 927 928 Return the given window's current background character/attribute pair. 929 930 931.. method:: window.getch([y, x]) 932 933 Get a character. Note that the integer returned does *not* have to be in ASCII 934 range: function keys, keypad keys and so on are represented by numbers higher 935 than 255. In no-delay mode, return ``-1`` if there is no input, otherwise 936 wait until a key is pressed. 937 938 939.. method:: window.get_wch([y, x]) 940 941 Get a wide character. Return a character for most keys, or an integer for 942 function keys, keypad keys, and other special keys. 943 In no-delay mode, raise an exception if there is no input. 944 945 .. versionadded:: 3.3 946 947 948.. method:: window.getkey([y, x]) 949 950 Get a character, returning a string instead of an integer, as :meth:`getch` 951 does. Function keys, keypad keys and other special keys return a multibyte 952 string containing the key name. In no-delay mode, raise an exception if 953 there is no input. 954 955 956.. method:: window.getmaxyx() 957 958 Return a tuple ``(y, x)`` of the height and width of the window. 959 960 961.. method:: window.getparyx() 962 963 Return the beginning coordinates of this window relative to its parent window 964 as a tuple ``(y, x)``. Return ``(-1, -1)`` if this window has no 965 parent. 966 967 968.. method:: window.getstr() 969 window.getstr(n) 970 window.getstr(y, x) 971 window.getstr(y, x, n) 972 973 Read a bytes object from the user, with primitive line editing capacity. 974 975 976.. method:: window.getyx() 977 978 Return a tuple ``(y, x)`` of current cursor position relative to the window's 979 upper-left corner. 980 981 982.. method:: window.hline(ch, n) 983 window.hline(y, x, ch, n) 984 985 Display a horizontal line starting at ``(y, x)`` with length *n* consisting of 986 the character *ch*. 987 988 989.. method:: window.idcok(flag) 990 991 If *flag* is ``False``, curses no longer considers using the hardware insert/delete 992 character feature of the terminal; if *flag* is ``True``, use of character insertion 993 and deletion is enabled. When curses is first initialized, use of character 994 insert/delete is enabled by default. 995 996 997.. method:: window.idlok(flag) 998 999 If *flag* is ``True``, :mod:`curses` will try and use hardware line 1000 editing facilities. Otherwise, line insertion/deletion are disabled. 1001 1002 1003.. method:: window.immedok(flag) 1004 1005 If *flag* is ``True``, any change in the window image automatically causes the 1006 window to be refreshed; you no longer have to call :meth:`refresh` yourself. 1007 However, it may degrade performance considerably, due to repeated calls to 1008 wrefresh. This option is disabled by default. 1009 1010 1011.. method:: window.inch([y, x]) 1012 1013 Return the character at the given position in the window. The bottom 8 bits are 1014 the character proper, and upper bits are the attributes. 1015 1016 1017.. method:: window.insch(ch[, attr]) 1018 window.insch(y, x, ch[, attr]) 1019 1020 Paint character *ch* at ``(y, x)`` with attributes *attr*, moving the line from 1021 position *x* right by one character. 1022 1023 1024.. method:: window.insdelln(nlines) 1025 1026 Insert *nlines* lines into the specified window above the current line. The 1027 *nlines* bottom lines are lost. For negative *nlines*, delete *nlines* lines 1028 starting with the one under the cursor, and move the remaining lines up. The 1029 bottom *nlines* lines are cleared. The current cursor position remains the 1030 same. 1031 1032 1033.. method:: window.insertln() 1034 1035 Insert a blank line under the cursor. All following lines are moved down by one 1036 line. 1037 1038 1039.. method:: window.insnstr(str, n[, attr]) 1040 window.insnstr(y, x, str, n[, attr]) 1041 1042 Insert a character string (as many characters as will fit on the line) before 1043 the character under the cursor, up to *n* characters. If *n* is zero or 1044 negative, the entire string is inserted. All characters to the right of the 1045 cursor are shifted right, with the rightmost characters on the line being lost. 1046 The cursor position does not change (after moving to *y*, *x*, if specified). 1047 1048 1049.. method:: window.insstr(str[, attr]) 1050 window.insstr(y, x, str[, attr]) 1051 1052 Insert a character string (as many characters as will fit on the line) before 1053 the character under the cursor. All characters to the right of the cursor are 1054 shifted right, with the rightmost characters on the line being lost. The cursor 1055 position does not change (after moving to *y*, *x*, if specified). 1056 1057 1058.. method:: window.instr([n]) 1059 window.instr(y, x[, n]) 1060 1061 Return a bytes object of characters, extracted from the window starting at the 1062 current cursor position, or at *y*, *x* if specified. Attributes are stripped 1063 from the characters. If *n* is specified, :meth:`instr` returns a string 1064 at most *n* characters long (exclusive of the trailing NUL). 1065 1066 1067.. method:: window.is_linetouched(line) 1068 1069 Return ``True`` if the specified line was modified since the last call to 1070 :meth:`refresh`; otherwise return ``False``. Raise a :exc:`curses.error` 1071 exception if *line* is not valid for the given window. 1072 1073 1074.. method:: window.is_wintouched() 1075 1076 Return ``True`` if the specified window was modified since the last call to 1077 :meth:`refresh`; otherwise return ``False``. 1078 1079 1080.. method:: window.keypad(flag) 1081 1082 If *flag* is ``True``, escape sequences generated by some keys (keypad, function keys) 1083 will be interpreted by :mod:`curses`. If *flag* is ``False``, escape sequences will be 1084 left as is in the input stream. 1085 1086 1087.. method:: window.leaveok(flag) 1088 1089 If *flag* is ``True``, cursor is left where it is on update, instead of being at "cursor 1090 position." This reduces cursor movement where possible. If possible the cursor 1091 will be made invisible. 1092 1093 If *flag* is ``False``, cursor will always be at "cursor position" after an update. 1094 1095 1096.. method:: window.move(new_y, new_x) 1097 1098 Move cursor to ``(new_y, new_x)``. 1099 1100 1101.. method:: window.mvderwin(y, x) 1102 1103 Move the window inside its parent window. The screen-relative parameters of 1104 the window are not changed. This routine is used to display different parts of 1105 the parent window at the same physical position on the screen. 1106 1107 1108.. method:: window.mvwin(new_y, new_x) 1109 1110 Move the window so its upper-left corner is at ``(new_y, new_x)``. 1111 1112 1113.. method:: window.nodelay(flag) 1114 1115 If *flag* is ``True``, :meth:`getch` will be non-blocking. 1116 1117 1118.. method:: window.notimeout(flag) 1119 1120 If *flag* is ``True``, escape sequences will not be timed out. 1121 1122 If *flag* is ``False``, after a few milliseconds, an escape sequence will not be 1123 interpreted, and will be left in the input stream as is. 1124 1125 1126.. method:: window.noutrefresh() 1127 1128 Mark for refresh but wait. This function updates the data structure 1129 representing the desired state of the window, but does not force an update of 1130 the physical screen. To accomplish that, call :func:`doupdate`. 1131 1132 1133.. method:: window.overlay(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol]) 1134 1135 Overlay the window on top of *destwin*. The windows need not be the same size, 1136 only the overlapping region is copied. This copy is non-destructive, which means 1137 that the current background character does not overwrite the old contents of 1138 *destwin*. 1139 1140 To get fine-grained control over the copied region, the second form of 1141 :meth:`overlay` can be used. *sminrow* and *smincol* are the upper-left 1142 coordinates of the source window, and the other variables mark a rectangle in 1143 the destination window. 1144 1145 1146.. method:: window.overwrite(destwin[, sminrow, smincol, dminrow, dmincol, dmaxrow, dmaxcol]) 1147 1148 Overwrite the window on top of *destwin*. The windows need not be the same size, 1149 in which case only the overlapping region is copied. This copy is destructive, 1150 which means that the current background character overwrites the old contents of 1151 *destwin*. 1152 1153 To get fine-grained control over the copied region, the second form of 1154 :meth:`overwrite` can be used. *sminrow* and *smincol* are the upper-left 1155 coordinates of the source window, the other variables mark a rectangle in the 1156 destination window. 1157 1158 1159.. method:: window.putwin(file) 1160 1161 Write all data associated with the window into the provided file object. This 1162 information can be later retrieved using the :func:`getwin` function. 1163 1164 1165.. method:: window.redrawln(beg, num) 1166 1167 Indicate that the *num* screen lines, starting at line *beg*, are corrupted and 1168 should be completely redrawn on the next :meth:`refresh` call. 1169 1170 1171.. method:: window.redrawwin() 1172 1173 Touch the entire window, causing it to be completely redrawn on the next 1174 :meth:`refresh` call. 1175 1176 1177.. method:: window.refresh([pminrow, pmincol, sminrow, smincol, smaxrow, smaxcol]) 1178 1179 Update the display immediately (sync actual screen with previous 1180 drawing/deleting methods). 1181 1182 The 6 optional arguments can only be specified when the window is a pad created 1183 with :func:`newpad`. The additional parameters are needed to indicate what part 1184 of the pad and screen are involved. *pminrow* and *pmincol* specify the upper 1185 left-hand corner of the rectangle to be displayed in the pad. *sminrow*, 1186 *smincol*, *smaxrow*, and *smaxcol* specify the edges of the rectangle to be 1187 displayed on the screen. The lower right-hand corner of the rectangle to be 1188 displayed in the pad is calculated from the screen coordinates, since the 1189 rectangles must be the same size. Both rectangles must be entirely contained 1190 within their respective structures. Negative values of *pminrow*, *pmincol*, 1191 *sminrow*, or *smincol* are treated as if they were zero. 1192 1193 1194.. method:: window.resize(nlines, ncols) 1195 1196 Reallocate storage for a curses window to adjust its dimensions to the 1197 specified values. If either dimension is larger than the current values, the 1198 window's data is filled with blanks that have the current background 1199 rendition (as set by :meth:`bkgdset`) merged into them. 1200 1201 1202.. method:: window.scroll([lines=1]) 1203 1204 Scroll the screen or scrolling region upward by *lines* lines. 1205 1206 1207.. method:: window.scrollok(flag) 1208 1209 Control what happens when the cursor of a window is moved off the edge of the 1210 window or scrolling region, either as a result of a newline action on the bottom 1211 line, or typing the last character of the last line. If *flag* is ``False``, the 1212 cursor is left on the bottom line. If *flag* is ``True``, the window is scrolled up 1213 one line. Note that in order to get the physical scrolling effect on the 1214 terminal, it is also necessary to call :meth:`idlok`. 1215 1216 1217.. method:: window.setscrreg(top, bottom) 1218 1219 Set the scrolling region from line *top* to line *bottom*. All scrolling actions 1220 will take place in this region. 1221 1222 1223.. method:: window.standend() 1224 1225 Turn off the standout attribute. On some terminals this has the side effect of 1226 turning off all attributes. 1227 1228 1229.. method:: window.standout() 1230 1231 Turn on attribute *A_STANDOUT*. 1232 1233 1234.. method:: window.subpad(begin_y, begin_x) 1235 window.subpad(nlines, ncols, begin_y, begin_x) 1236 1237 Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and 1238 whose width/height is *ncols*/*nlines*. 1239 1240 1241.. method:: window.subwin(begin_y, begin_x) 1242 window.subwin(nlines, ncols, begin_y, begin_x) 1243 1244 Return a sub-window, whose upper-left corner is at ``(begin_y, begin_x)``, and 1245 whose width/height is *ncols*/*nlines*. 1246 1247 By default, the sub-window will extend from the specified position to the lower 1248 right corner of the window. 1249 1250 1251.. method:: window.syncdown() 1252 1253 Touch each location in the window that has been touched in any of its ancestor 1254 windows. This routine is called by :meth:`refresh`, so it should almost never 1255 be necessary to call it manually. 1256 1257 1258.. method:: window.syncok(flag) 1259 1260 If *flag* is ``True``, then :meth:`syncup` is called automatically 1261 whenever there is a change in the window. 1262 1263 1264.. method:: window.syncup() 1265 1266 Touch all locations in ancestors of the window that have been changed in the 1267 window. 1268 1269 1270.. method:: window.timeout(delay) 1271 1272 Set blocking or non-blocking read behavior for the window. If *delay* is 1273 negative, blocking read is used (which will wait indefinitely for input). If 1274 *delay* is zero, then non-blocking read is used, and :meth:`getch` will 1275 return ``-1`` if no input is waiting. If *delay* is positive, then 1276 :meth:`getch` will block for *delay* milliseconds, and return ``-1`` if there is 1277 still no input at the end of that time. 1278 1279 1280.. method:: window.touchline(start, count[, changed]) 1281 1282 Pretend *count* lines have been changed, starting with line *start*. If 1283 *changed* is supplied, it specifies whether the affected lines are marked as 1284 having been changed (*changed*\ ``=True``) or unchanged (*changed*\ ``=False``). 1285 1286 1287.. method:: window.touchwin() 1288 1289 Pretend the whole window has been changed, for purposes of drawing 1290 optimizations. 1291 1292 1293.. method:: window.untouchwin() 1294 1295 Mark all lines in the window as unchanged since the last call to 1296 :meth:`refresh`. 1297 1298 1299.. method:: window.vline(ch, n) 1300 window.vline(y, x, ch, n) 1301 1302 Display a vertical line starting at ``(y, x)`` with length *n* consisting of the 1303 character *ch*. 1304 1305 1306Constants 1307--------- 1308 1309The :mod:`curses` module defines the following data members: 1310 1311 1312.. data:: ERR 1313 1314 Some curses routines that return an integer, such as :meth:`~window.getch`, return 1315 :const:`ERR` upon failure. 1316 1317 1318.. data:: OK 1319 1320 Some curses routines that return an integer, such as :func:`napms`, return 1321 :const:`OK` upon success. 1322 1323 1324.. data:: version 1325 1326 A bytes object representing the current version of the module. Also available as 1327 :const:`__version__`. 1328 1329 1330.. data:: ncurses_version 1331 1332 A named tuple containing the three components of the ncurses library 1333 version: *major*, *minor*, and *patch*. All values are integers. The 1334 components can also be accessed by name, so ``curses.ncurses_version[0]`` 1335 is equivalent to ``curses.ncurses_version.major`` and so on. 1336 1337 Availability: if the ncurses library is used. 1338 1339 .. versionadded:: 3.8 1340 1341 1342Some constants are available to specify character cell attributes. 1343The exact constants available are system dependent. 1344 1345+------------------+-------------------------------+ 1346| Attribute | Meaning | 1347+==================+===============================+ 1348| ``A_ALTCHARSET`` | Alternate character set mode | 1349+------------------+-------------------------------+ 1350| ``A_BLINK`` | Blink mode | 1351+------------------+-------------------------------+ 1352| ``A_BOLD`` | Bold mode | 1353+------------------+-------------------------------+ 1354| ``A_DIM`` | Dim mode | 1355+------------------+-------------------------------+ 1356| ``A_INVIS`` | Invisible or blank mode | 1357+------------------+-------------------------------+ 1358| ``A_ITALIC`` | Italic mode | 1359+------------------+-------------------------------+ 1360| ``A_NORMAL`` | Normal attribute | 1361+------------------+-------------------------------+ 1362| ``A_PROTECT`` | Protected mode | 1363+------------------+-------------------------------+ 1364| ``A_REVERSE`` | Reverse background and | 1365| | foreground colors | 1366+------------------+-------------------------------+ 1367| ``A_STANDOUT`` | Standout mode | 1368+------------------+-------------------------------+ 1369| ``A_UNDERLINE`` | Underline mode | 1370+------------------+-------------------------------+ 1371| ``A_HORIZONTAL`` | Horizontal highlight | 1372+------------------+-------------------------------+ 1373| ``A_LEFT`` | Left highlight | 1374+------------------+-------------------------------+ 1375| ``A_LOW`` | Low highlight | 1376+------------------+-------------------------------+ 1377| ``A_RIGHT`` | Right highlight | 1378+------------------+-------------------------------+ 1379| ``A_TOP`` | Top highlight | 1380+------------------+-------------------------------+ 1381| ``A_VERTICAL`` | Vertical highlight | 1382+------------------+-------------------------------+ 1383| ``A_CHARTEXT`` | Bit-mask to extract a | 1384| | character | 1385+------------------+-------------------------------+ 1386 1387.. versionadded:: 3.7 1388 ``A_ITALIC`` was added. 1389 1390Several constants are available to extract corresponding attributes returned 1391by some methods. 1392 1393+------------------+-------------------------------+ 1394| Bit-mask | Meaning | 1395+==================+===============================+ 1396| ``A_ATTRIBUTES`` | Bit-mask to extract | 1397| | attributes | 1398+------------------+-------------------------------+ 1399| ``A_CHARTEXT`` | Bit-mask to extract a | 1400| | character | 1401+------------------+-------------------------------+ 1402| ``A_COLOR`` | Bit-mask to extract | 1403| | color-pair field information | 1404+------------------+-------------------------------+ 1405 1406Keys are referred to by integer constants with names starting with ``KEY_``. 1407The exact keycaps available are system dependent. 1408 1409.. XXX this table is far too large! should it be alphabetized? 1410 1411+-------------------+--------------------------------------------+ 1412| Key constant | Key | 1413+===================+============================================+ 1414| ``KEY_MIN`` | Minimum key value | 1415+-------------------+--------------------------------------------+ 1416| ``KEY_BREAK`` | Break key (unreliable) | 1417+-------------------+--------------------------------------------+ 1418| ``KEY_DOWN`` | Down-arrow | 1419+-------------------+--------------------------------------------+ 1420| ``KEY_UP`` | Up-arrow | 1421+-------------------+--------------------------------------------+ 1422| ``KEY_LEFT`` | Left-arrow | 1423+-------------------+--------------------------------------------+ 1424| ``KEY_RIGHT`` | Right-arrow | 1425+-------------------+--------------------------------------------+ 1426| ``KEY_HOME`` | Home key (upward+left arrow) | 1427+-------------------+--------------------------------------------+ 1428| ``KEY_BACKSPACE`` | Backspace (unreliable) | 1429+-------------------+--------------------------------------------+ 1430| ``KEY_F0`` | Function keys. Up to 64 function keys are | 1431| | supported. | 1432+-------------------+--------------------------------------------+ 1433| ``KEY_Fn`` | Value of function key *n* | 1434+-------------------+--------------------------------------------+ 1435| ``KEY_DL`` | Delete line | 1436+-------------------+--------------------------------------------+ 1437| ``KEY_IL`` | Insert line | 1438+-------------------+--------------------------------------------+ 1439| ``KEY_DC`` | Delete character | 1440+-------------------+--------------------------------------------+ 1441| ``KEY_IC`` | Insert char or enter insert mode | 1442+-------------------+--------------------------------------------+ 1443| ``KEY_EIC`` | Exit insert char mode | 1444+-------------------+--------------------------------------------+ 1445| ``KEY_CLEAR`` | Clear screen | 1446+-------------------+--------------------------------------------+ 1447| ``KEY_EOS`` | Clear to end of screen | 1448+-------------------+--------------------------------------------+ 1449| ``KEY_EOL`` | Clear to end of line | 1450+-------------------+--------------------------------------------+ 1451| ``KEY_SF`` | Scroll 1 line forward | 1452+-------------------+--------------------------------------------+ 1453| ``KEY_SR`` | Scroll 1 line backward (reverse) | 1454+-------------------+--------------------------------------------+ 1455| ``KEY_NPAGE`` | Next page | 1456+-------------------+--------------------------------------------+ 1457| ``KEY_PPAGE`` | Previous page | 1458+-------------------+--------------------------------------------+ 1459| ``KEY_STAB`` | Set tab | 1460+-------------------+--------------------------------------------+ 1461| ``KEY_CTAB`` | Clear tab | 1462+-------------------+--------------------------------------------+ 1463| ``KEY_CATAB`` | Clear all tabs | 1464+-------------------+--------------------------------------------+ 1465| ``KEY_ENTER`` | Enter or send (unreliable) | 1466+-------------------+--------------------------------------------+ 1467| ``KEY_SRESET`` | Soft (partial) reset (unreliable) | 1468+-------------------+--------------------------------------------+ 1469| ``KEY_RESET`` | Reset or hard reset (unreliable) | 1470+-------------------+--------------------------------------------+ 1471| ``KEY_PRINT`` | Print | 1472+-------------------+--------------------------------------------+ 1473| ``KEY_LL`` | Home down or bottom (lower left) | 1474+-------------------+--------------------------------------------+ 1475| ``KEY_A1`` | Upper left of keypad | 1476+-------------------+--------------------------------------------+ 1477| ``KEY_A3`` | Upper right of keypad | 1478+-------------------+--------------------------------------------+ 1479| ``KEY_B2`` | Center of keypad | 1480+-------------------+--------------------------------------------+ 1481| ``KEY_C1`` | Lower left of keypad | 1482+-------------------+--------------------------------------------+ 1483| ``KEY_C3`` | Lower right of keypad | 1484+-------------------+--------------------------------------------+ 1485| ``KEY_BTAB`` | Back tab | 1486+-------------------+--------------------------------------------+ 1487| ``KEY_BEG`` | Beg (beginning) | 1488+-------------------+--------------------------------------------+ 1489| ``KEY_CANCEL`` | Cancel | 1490+-------------------+--------------------------------------------+ 1491| ``KEY_CLOSE`` | Close | 1492+-------------------+--------------------------------------------+ 1493| ``KEY_COMMAND`` | Cmd (command) | 1494+-------------------+--------------------------------------------+ 1495| ``KEY_COPY`` | Copy | 1496+-------------------+--------------------------------------------+ 1497| ``KEY_CREATE`` | Create | 1498+-------------------+--------------------------------------------+ 1499| ``KEY_END`` | End | 1500+-------------------+--------------------------------------------+ 1501| ``KEY_EXIT`` | Exit | 1502+-------------------+--------------------------------------------+ 1503| ``KEY_FIND`` | Find | 1504+-------------------+--------------------------------------------+ 1505| ``KEY_HELP`` | Help | 1506+-------------------+--------------------------------------------+ 1507| ``KEY_MARK`` | Mark | 1508+-------------------+--------------------------------------------+ 1509| ``KEY_MESSAGE`` | Message | 1510+-------------------+--------------------------------------------+ 1511| ``KEY_MOVE`` | Move | 1512+-------------------+--------------------------------------------+ 1513| ``KEY_NEXT`` | Next | 1514+-------------------+--------------------------------------------+ 1515| ``KEY_OPEN`` | Open | 1516+-------------------+--------------------------------------------+ 1517| ``KEY_OPTIONS`` | Options | 1518+-------------------+--------------------------------------------+ 1519| ``KEY_PREVIOUS`` | Prev (previous) | 1520+-------------------+--------------------------------------------+ 1521| ``KEY_REDO`` | Redo | 1522+-------------------+--------------------------------------------+ 1523| ``KEY_REFERENCE`` | Ref (reference) | 1524+-------------------+--------------------------------------------+ 1525| ``KEY_REFRESH`` | Refresh | 1526+-------------------+--------------------------------------------+ 1527| ``KEY_REPLACE`` | Replace | 1528+-------------------+--------------------------------------------+ 1529| ``KEY_RESTART`` | Restart | 1530+-------------------+--------------------------------------------+ 1531| ``KEY_RESUME`` | Resume | 1532+-------------------+--------------------------------------------+ 1533| ``KEY_SAVE`` | Save | 1534+-------------------+--------------------------------------------+ 1535| ``KEY_SBEG`` | Shifted Beg (beginning) | 1536+-------------------+--------------------------------------------+ 1537| ``KEY_SCANCEL`` | Shifted Cancel | 1538+-------------------+--------------------------------------------+ 1539| ``KEY_SCOMMAND`` | Shifted Command | 1540+-------------------+--------------------------------------------+ 1541| ``KEY_SCOPY`` | Shifted Copy | 1542+-------------------+--------------------------------------------+ 1543| ``KEY_SCREATE`` | Shifted Create | 1544+-------------------+--------------------------------------------+ 1545| ``KEY_SDC`` | Shifted Delete char | 1546+-------------------+--------------------------------------------+ 1547| ``KEY_SDL`` | Shifted Delete line | 1548+-------------------+--------------------------------------------+ 1549| ``KEY_SELECT`` | Select | 1550+-------------------+--------------------------------------------+ 1551| ``KEY_SEND`` | Shifted End | 1552+-------------------+--------------------------------------------+ 1553| ``KEY_SEOL`` | Shifted Clear line | 1554+-------------------+--------------------------------------------+ 1555| ``KEY_SEXIT`` | Shifted Exit | 1556+-------------------+--------------------------------------------+ 1557| ``KEY_SFIND`` | Shifted Find | 1558+-------------------+--------------------------------------------+ 1559| ``KEY_SHELP`` | Shifted Help | 1560+-------------------+--------------------------------------------+ 1561| ``KEY_SHOME`` | Shifted Home | 1562+-------------------+--------------------------------------------+ 1563| ``KEY_SIC`` | Shifted Input | 1564+-------------------+--------------------------------------------+ 1565| ``KEY_SLEFT`` | Shifted Left arrow | 1566+-------------------+--------------------------------------------+ 1567| ``KEY_SMESSAGE`` | Shifted Message | 1568+-------------------+--------------------------------------------+ 1569| ``KEY_SMOVE`` | Shifted Move | 1570+-------------------+--------------------------------------------+ 1571| ``KEY_SNEXT`` | Shifted Next | 1572+-------------------+--------------------------------------------+ 1573| ``KEY_SOPTIONS`` | Shifted Options | 1574+-------------------+--------------------------------------------+ 1575| ``KEY_SPREVIOUS`` | Shifted Prev | 1576+-------------------+--------------------------------------------+ 1577| ``KEY_SPRINT`` | Shifted Print | 1578+-------------------+--------------------------------------------+ 1579| ``KEY_SREDO`` | Shifted Redo | 1580+-------------------+--------------------------------------------+ 1581| ``KEY_SREPLACE`` | Shifted Replace | 1582+-------------------+--------------------------------------------+ 1583| ``KEY_SRIGHT`` | Shifted Right arrow | 1584+-------------------+--------------------------------------------+ 1585| ``KEY_SRSUME`` | Shifted Resume | 1586+-------------------+--------------------------------------------+ 1587| ``KEY_SSAVE`` | Shifted Save | 1588+-------------------+--------------------------------------------+ 1589| ``KEY_SSUSPEND`` | Shifted Suspend | 1590+-------------------+--------------------------------------------+ 1591| ``KEY_SUNDO`` | Shifted Undo | 1592+-------------------+--------------------------------------------+ 1593| ``KEY_SUSPEND`` | Suspend | 1594+-------------------+--------------------------------------------+ 1595| ``KEY_UNDO`` | Undo | 1596+-------------------+--------------------------------------------+ 1597| ``KEY_MOUSE`` | Mouse event has occurred | 1598+-------------------+--------------------------------------------+ 1599| ``KEY_RESIZE`` | Terminal resize event | 1600+-------------------+--------------------------------------------+ 1601| ``KEY_MAX`` | Maximum key value | 1602+-------------------+--------------------------------------------+ 1603 1604On VT100s and their software emulations, such as X terminal emulators, there are 1605normally at least four function keys (:const:`KEY_F1`, :const:`KEY_F2`, 1606:const:`KEY_F3`, :const:`KEY_F4`) available, and the arrow keys mapped to 1607:const:`KEY_UP`, :const:`KEY_DOWN`, :const:`KEY_LEFT` and :const:`KEY_RIGHT` in 1608the obvious way. If your machine has a PC keyboard, it is safe to expect arrow 1609keys and twelve function keys (older PC keyboards may have only ten function 1610keys); also, the following keypad mappings are standard: 1611 1612+------------------+-----------+ 1613| Keycap | Constant | 1614+==================+===========+ 1615| :kbd:`Insert` | KEY_IC | 1616+------------------+-----------+ 1617| :kbd:`Delete` | KEY_DC | 1618+------------------+-----------+ 1619| :kbd:`Home` | KEY_HOME | 1620+------------------+-----------+ 1621| :kbd:`End` | KEY_END | 1622+------------------+-----------+ 1623| :kbd:`Page Up` | KEY_PPAGE | 1624+------------------+-----------+ 1625| :kbd:`Page Down` | KEY_NPAGE | 1626+------------------+-----------+ 1627 1628The following table lists characters from the alternate character set. These are 1629inherited from the VT100 terminal, and will generally be available on software 1630emulations such as X terminals. When there is no graphic available, curses 1631falls back on a crude printable ASCII approximation. 1632 1633.. note:: 1634 1635 These are available only after :func:`initscr` has been called. 1636 1637+------------------+------------------------------------------+ 1638| ACS code | Meaning | 1639+==================+==========================================+ 1640| ``ACS_BBSS`` | alternate name for upper right corner | 1641+------------------+------------------------------------------+ 1642| ``ACS_BLOCK`` | solid square block | 1643+------------------+------------------------------------------+ 1644| ``ACS_BOARD`` | board of squares | 1645+------------------+------------------------------------------+ 1646| ``ACS_BSBS`` | alternate name for horizontal line | 1647+------------------+------------------------------------------+ 1648| ``ACS_BSSB`` | alternate name for upper left corner | 1649+------------------+------------------------------------------+ 1650| ``ACS_BSSS`` | alternate name for top tee | 1651+------------------+------------------------------------------+ 1652| ``ACS_BTEE`` | bottom tee | 1653+------------------+------------------------------------------+ 1654| ``ACS_BULLET`` | bullet | 1655+------------------+------------------------------------------+ 1656| ``ACS_CKBOARD`` | checker board (stipple) | 1657+------------------+------------------------------------------+ 1658| ``ACS_DARROW`` | arrow pointing down | 1659+------------------+------------------------------------------+ 1660| ``ACS_DEGREE`` | degree symbol | 1661+------------------+------------------------------------------+ 1662| ``ACS_DIAMOND`` | diamond | 1663+------------------+------------------------------------------+ 1664| ``ACS_GEQUAL`` | greater-than-or-equal-to | 1665+------------------+------------------------------------------+ 1666| ``ACS_HLINE`` | horizontal line | 1667+------------------+------------------------------------------+ 1668| ``ACS_LANTERN`` | lantern symbol | 1669+------------------+------------------------------------------+ 1670| ``ACS_LARROW`` | left arrow | 1671+------------------+------------------------------------------+ 1672| ``ACS_LEQUAL`` | less-than-or-equal-to | 1673+------------------+------------------------------------------+ 1674| ``ACS_LLCORNER`` | lower left-hand corner | 1675+------------------+------------------------------------------+ 1676| ``ACS_LRCORNER`` | lower right-hand corner | 1677+------------------+------------------------------------------+ 1678| ``ACS_LTEE`` | left tee | 1679+------------------+------------------------------------------+ 1680| ``ACS_NEQUAL`` | not-equal sign | 1681+------------------+------------------------------------------+ 1682| ``ACS_PI`` | letter pi | 1683+------------------+------------------------------------------+ 1684| ``ACS_PLMINUS`` | plus-or-minus sign | 1685+------------------+------------------------------------------+ 1686| ``ACS_PLUS`` | big plus sign | 1687+------------------+------------------------------------------+ 1688| ``ACS_RARROW`` | right arrow | 1689+------------------+------------------------------------------+ 1690| ``ACS_RTEE`` | right tee | 1691+------------------+------------------------------------------+ 1692| ``ACS_S1`` | scan line 1 | 1693+------------------+------------------------------------------+ 1694| ``ACS_S3`` | scan line 3 | 1695+------------------+------------------------------------------+ 1696| ``ACS_S7`` | scan line 7 | 1697+------------------+------------------------------------------+ 1698| ``ACS_S9`` | scan line 9 | 1699+------------------+------------------------------------------+ 1700| ``ACS_SBBS`` | alternate name for lower right corner | 1701+------------------+------------------------------------------+ 1702| ``ACS_SBSB`` | alternate name for vertical line | 1703+------------------+------------------------------------------+ 1704| ``ACS_SBSS`` | alternate name for right tee | 1705+------------------+------------------------------------------+ 1706| ``ACS_SSBB`` | alternate name for lower left corner | 1707+------------------+------------------------------------------+ 1708| ``ACS_SSBS`` | alternate name for bottom tee | 1709+------------------+------------------------------------------+ 1710| ``ACS_SSSB`` | alternate name for left tee | 1711+------------------+------------------------------------------+ 1712| ``ACS_SSSS`` | alternate name for crossover or big plus | 1713+------------------+------------------------------------------+ 1714| ``ACS_STERLING`` | pound sterling | 1715+------------------+------------------------------------------+ 1716| ``ACS_TTEE`` | top tee | 1717+------------------+------------------------------------------+ 1718| ``ACS_UARROW`` | up arrow | 1719+------------------+------------------------------------------+ 1720| ``ACS_ULCORNER`` | upper left corner | 1721+------------------+------------------------------------------+ 1722| ``ACS_URCORNER`` | upper right corner | 1723+------------------+------------------------------------------+ 1724| ``ACS_VLINE`` | vertical line | 1725+------------------+------------------------------------------+ 1726 1727The following table lists the predefined colors: 1728 1729+-------------------+----------------------------+ 1730| Constant | Color | 1731+===================+============================+ 1732| ``COLOR_BLACK`` | Black | 1733+-------------------+----------------------------+ 1734| ``COLOR_BLUE`` | Blue | 1735+-------------------+----------------------------+ 1736| ``COLOR_CYAN`` | Cyan (light greenish blue) | 1737+-------------------+----------------------------+ 1738| ``COLOR_GREEN`` | Green | 1739+-------------------+----------------------------+ 1740| ``COLOR_MAGENTA`` | Magenta (purplish red) | 1741+-------------------+----------------------------+ 1742| ``COLOR_RED`` | Red | 1743+-------------------+----------------------------+ 1744| ``COLOR_WHITE`` | White | 1745+-------------------+----------------------------+ 1746| ``COLOR_YELLOW`` | Yellow | 1747+-------------------+----------------------------+ 1748 1749 1750:mod:`curses.textpad` --- Text input widget for curses programs 1751=============================================================== 1752 1753.. module:: curses.textpad 1754 :synopsis: Emacs-like input editing in a curses window. 1755.. moduleauthor:: Eric Raymond <esr@thyrsus.com> 1756.. sectionauthor:: Eric Raymond <esr@thyrsus.com> 1757 1758 1759The :mod:`curses.textpad` module provides a :class:`Textbox` class that handles 1760elementary text editing in a curses window, supporting a set of keybindings 1761resembling those of Emacs (thus, also of Netscape Navigator, BBedit 6.x, 1762FrameMaker, and many other programs). The module also provides a 1763rectangle-drawing function useful for framing text boxes or for other purposes. 1764 1765The module :mod:`curses.textpad` defines the following function: 1766 1767 1768.. function:: rectangle(win, uly, ulx, lry, lrx) 1769 1770 Draw a rectangle. The first argument must be a window object; the remaining 1771 arguments are coordinates relative to that window. The second and third 1772 arguments are the y and x coordinates of the upper left hand corner of the 1773 rectangle to be drawn; the fourth and fifth arguments are the y and x 1774 coordinates of the lower right hand corner. The rectangle will be drawn using 1775 VT100/IBM PC forms characters on terminals that make this possible (including 1776 xterm and most other software terminal emulators). Otherwise it will be drawn 1777 with ASCII dashes, vertical bars, and plus signs. 1778 1779 1780.. _curses-textpad-objects: 1781 1782Textbox objects 1783--------------- 1784 1785You can instantiate a :class:`Textbox` object as follows: 1786 1787 1788.. class:: Textbox(win) 1789 1790 Return a textbox widget object. The *win* argument should be a curses 1791 :ref:`window <curses-window-objects>` object in which the textbox is to 1792 be contained. The edit cursor of the textbox is initially located at the 1793 upper left hand corner of the containing window, with coordinates ``(0, 0)``. 1794 The instance's :attr:`stripspaces` flag is initially on. 1795 1796 :class:`Textbox` objects have the following methods: 1797 1798 1799 .. method:: edit([validator]) 1800 1801 This is the entry point you will normally use. It accepts editing 1802 keystrokes until one of the termination keystrokes is entered. If 1803 *validator* is supplied, it must be a function. It will be called for 1804 each keystroke entered with the keystroke as a parameter; command dispatch 1805 is done on the result. This method returns the window contents as a 1806 string; whether blanks in the window are included is affected by the 1807 :attr:`stripspaces` attribute. 1808 1809 1810 .. method:: do_command(ch) 1811 1812 Process a single command keystroke. Here are the supported special 1813 keystrokes: 1814 1815 +------------------+-------------------------------------------+ 1816 | Keystroke | Action | 1817 +==================+===========================================+ 1818 | :kbd:`Control-A` | Go to left edge of window. | 1819 +------------------+-------------------------------------------+ 1820 | :kbd:`Control-B` | Cursor left, wrapping to previous line if | 1821 | | appropriate. | 1822 +------------------+-------------------------------------------+ 1823 | :kbd:`Control-D` | Delete character under cursor. | 1824 +------------------+-------------------------------------------+ 1825 | :kbd:`Control-E` | Go to right edge (stripspaces off) or end | 1826 | | of line (stripspaces on). | 1827 +------------------+-------------------------------------------+ 1828 | :kbd:`Control-F` | Cursor right, wrapping to next line when | 1829 | | appropriate. | 1830 +------------------+-------------------------------------------+ 1831 | :kbd:`Control-G` | Terminate, returning the window contents. | 1832 +------------------+-------------------------------------------+ 1833 | :kbd:`Control-H` | Delete character backward. | 1834 +------------------+-------------------------------------------+ 1835 | :kbd:`Control-J` | Terminate if the window is 1 line, | 1836 | | otherwise insert newline. | 1837 +------------------+-------------------------------------------+ 1838 | :kbd:`Control-K` | If line is blank, delete it, otherwise | 1839 | | clear to end of line. | 1840 +------------------+-------------------------------------------+ 1841 | :kbd:`Control-L` | Refresh screen. | 1842 +------------------+-------------------------------------------+ 1843 | :kbd:`Control-N` | Cursor down; move down one line. | 1844 +------------------+-------------------------------------------+ 1845 | :kbd:`Control-O` | Insert a blank line at cursor location. | 1846 +------------------+-------------------------------------------+ 1847 | :kbd:`Control-P` | Cursor up; move up one line. | 1848 +------------------+-------------------------------------------+ 1849 1850 Move operations do nothing if the cursor is at an edge where the movement 1851 is not possible. The following synonyms are supported where possible: 1852 1853 +------------------------+------------------+ 1854 | Constant | Keystroke | 1855 +========================+==================+ 1856 | :const:`KEY_LEFT` | :kbd:`Control-B` | 1857 +------------------------+------------------+ 1858 | :const:`KEY_RIGHT` | :kbd:`Control-F` | 1859 +------------------------+------------------+ 1860 | :const:`KEY_UP` | :kbd:`Control-P` | 1861 +------------------------+------------------+ 1862 | :const:`KEY_DOWN` | :kbd:`Control-N` | 1863 +------------------------+------------------+ 1864 | :const:`KEY_BACKSPACE` | :kbd:`Control-h` | 1865 +------------------------+------------------+ 1866 1867 All other keystrokes are treated as a command to insert the given 1868 character and move right (with line wrapping). 1869 1870 1871 .. method:: gather() 1872 1873 Return the window contents as a string; whether blanks in the 1874 window are included is affected by the :attr:`stripspaces` member. 1875 1876 1877 .. attribute:: stripspaces 1878 1879 This attribute is a flag which controls the interpretation of blanks in 1880 the window. When it is on, trailing blanks on each line are ignored; any 1881 cursor motion that would land the cursor on a trailing blank goes to the 1882 end of that line instead, and trailing blanks are stripped when the window 1883 contents are gathered. 1884