X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fncurses.3x.html;h=f473109097d1244c8f32af52544c62b63bbbe03b;hp=2382f1111a70664f4ff01057ef8bde1478b27a52;hb=HEAD;hpb=74137fec04e130a88ef25618cf730af988a4f51a;ds=sidebyside diff --git a/doc/html/man/ncurses.3x.html b/doc/html/man/ncurses.3x.html index 2382f111..e36b0fce 100644 --- a/doc/html/man/ncurses.3x.html +++ b/doc/html/man/ncurses.3x.html @@ -1,7 +1,8 @@ -
--ncurses(3x) ncurses(3x) +ncurses(3x) Library calls ncurses(3x)
- ncurses - CRT screen handling and optimization package + ncurses - character-cell terminal interface with optimized output
@@ -55,244 +56,282 @@
- The ncurses library routines give the user a terminal-independent - method of updating character screens with reasonable optimization. - This implementation is "new curses" (ncurses) and is the approved - replacement for 4.4BSD classic curses, which has been discontinued. - This describes ncurses version 6.1 (patch 20180331). - - The ncurses library emulates the curses library of System V Release 4 - UNIX, and XPG4 (X/Open Portability Guide) curses (also known as XSI - curses). XSI stands for X/Open System Interfaces Extension. The - ncurses library is freely redistributable in source form. Differences - from the SVr4 curses are summarized under the EXTENSIONS and PORTABIL- - ITY sections below and described in detail in the respective EXTEN- - SIONS, PORTABILITY and BUGS sections of individual man pages. - - The ncurses library also provides many useful extensions, i.e., fea- - tures which cannot be implemented by a simple add-on library but which - require access to the internals of the library. - - A program using these routines must be linked with the -lncurses - option, or (if it has been generated) with the debugging library - -lncurses_g. (Your system integrator may also have installed these - libraries under the names -lcurses and -lcurses_g.) The ncurses_g - library generates trace logs (in a file called 'trace' in the current - directory) that describe curses actions. See also the section on - ALTERNATE CONFIGURATIONS. - - The ncurses package supports: overall screen, window and pad manipula- - tion; output to windows and pads; reading terminal input; control over - terminal and curses input and output options; environment query rou- - tines; color manipulation; use of soft label keys; terminfo capabili- - ties; and access to low-level terminal-manipulation routines. + The "new curses" library offers the programmer a terminal-independent + means of reading keyboard and mouse input and updating character-cell + terminals with output optimized to minimize screen updates. ncurses + replaces the curses libraries from System V Release 4 Unix ("SVr4") and + 4.4BSD Unix, the development of which ceased in the 1990s. This + document describes ncurses version 6.5 (patch 20240525). + + ncurses permits control of the terminal screen's contents; abstraction + and subdivision thereof with windows and pads; acquisition of keyboard + and mouse events; control of terminal input and output options; + selection of color and rendering attributes (such as bold or + underline); the definition and use of soft label keys; access to the + terminfo terminal capability database; a termcap compatibility + interface; and an abstraction of the system's API for manipulating the + terminal (such as termios(3)). + + ncurses implements the interface described by X/Open Curses Issue 7. + In many behavioral details not standardized by X/Open, ncurses emulates + the curses library of SVr4 and provides numerous useful extensions. + + ncurses man pages employ several sections to clarify matters of usage + and interoperability with other curses implementations. + + o "NOTES" describes issues and caveats of which any user of the + ncurses API should be aware, such as limitations on the size of an + underlying integral type or the availability of a preprocessor + macro exclusive of a function definition (which prevents its + address from being taken). This section also describes + implementation details that will be significant to the programmer + but which are not standardized. + + o "EXTENSIONS" presents ncurses innovations beyond the X/Open Curses + standard and/or the SVr4 curses implementation. They are termed + extensions to indicate that they cannot be implemented solely by + using the library API, but require access to the library's internal + state. + + o "PORTABILITY" discusses matters (beyond the exercise of extensions) + that should be considered when writing to a curses standard, or for + multiple implementations. + + o "HISTORY" examines points of detail in ncurses and other curses + implementations over the decades of their development, particularly + where precedent or inertia have frustrated better design (and, in a + few cases, where such inertia has been overcome). + + A curses application must be linked with the library; use the -lncurses + option to your compiler or linker. A debugging version of the library + may be available; if so, link with it using -lncurses_g. (Your system + integrator may have installed these libraries such that you can use the + options -lcurses and -lcurses_g, respectively.) The ncurses_g library + generates trace logs (in a file called trace in the current directory) + that describe ncurses actions. See section "ALTERNATE CONFIGURATIONS" + below. + + +
+ A curses application uses information from the system locale; + setlocale(3) prepares it for curses library calls. + + setlocale(LC_ALL, ""); + + If the locale is not thus initialized, the library assumes that + characters are printable as in ISO 8859-1, to work with certain legacy + programs. You should initialize the locale; do not expect consistent + behavior from the library when the locale has not been set up. + + initscr(3x) or newterm(3x) must be called to initialize curses before + use of any functions that deal with windows and screens. + + To get character-at-a-time input without echoing--most interactive, + screen-oriented programs want this--use the following sequence. + + initscr(); cbreak(); noecho(); + + Most applications would perform further setup as follows. + + noqiflush(); + keypad(stdscr, TRUE); + + A curses program then often enters an event loop of some sort. Call + endwin(3x) before exiting. + + +
+ A curses library abstracts the terminal screen by representing all or + part of it as a WINDOW data structure. A window is a rectangular grid + of character cells, addressed by row and column coordinates (y, x), + with the upper left corner as (0, 0). A window called stdscr, the same + size as the terminal screen, is always available. Create others with + newwin(3x). + + A curses library does not manage overlapping windows (but see below). + You can either use stdscr to manage one screen-filling window, or tile + the screen into non-overlapping windows and not use stdscr at all. + Mixing the two approaches will result in unpredictable and undesired + effects. + + Functions permit manipulation of a window and the cursor identifying + the cell within it at which the next output operation will occur. + Among those, the most basic are move(3x) and addch(3x): these place the + cursor and write a character to stdscr, respectively. + + Frequent changes to the terminal screen can cause unpleasant flicker or + inefficient use of the communication channel to the device, so as a + rule the library does not update it automatically. Therefore, after + using curses functions to accumulate a set of desired updates that make + sense to present together, call refresh(3x) to tell the library to make + the user's screen look like stdscr. The library optimizes its output + by computing a minimal volume of operations to mutate the screen from + its state at the previous refresh to the new one. Effective + optimization demands accurate information about the terminal device: + the management of such information is the province of the terminfo(3x) + API, a feature of every standard curses implementation. + + Special windows called pads may also be manipulated. These are not + constrained to the size of the terminal screen and their contents need + not be completely displayed. See curs_pad(3x). + + Many terminals support configuration of character cell foreground and + background colors as well as attributes, which cause characters to + render in such modes as boldfaced, underlined, or in reverse video. + See curs_attr(3x). + + curses predefines constants for a small set of forms-drawing graphics + corresponding to the DEC Alternate Character Set (ACS), a feature of + VT100 and other terminals. See addch(3x). + + curses is implemented using the operating system's terminal driver; key + events are received not as scan codes but as byte sequences. Graphical + keycaps (alphanumeric and punctuation keys, and the space) appear as- + is. Everything else, including the tab, enter/return, keypad, arrow, + and function keys, appears as a control character or a multibyte escape + sequence. curses can translate the latter into unique key codes. See + keypad(3x) and getch(3x). + + ncurses provides reimplementations of the SVr4 panel(3x), form(3x), and + menu(3x) libraries; they permit overlapping windows and ease + construction of user interfaces with curses.
- The library uses the locale which the calling program has initialized. - That is normally done with setlocale: - - setlocale(LC_ALL, ""); - - If the locale is not initialized, the library assumes that characters - are printable as in ISO-8859-1, to work with certain legacy programs. - You should initialize the locale and not rely on specific details of - the library when the locale has not been setup. - - The function initscr or newterm must be called to initialize the - library before any of the other routines that deal with windows and - screens are used. The routine endwin(3x) must be called before exit- - ing. - - To get character-at-a-time input without echoing (most interactive, - screen oriented programs want this), the following sequence should be - used: - - initscr(); cbreak(); noecho(); - - Most programs would additionally use the sequence: - - nonl(); - intrflush(stdscr, FALSE); - keypad(stdscr, TRUE); - - Before a curses program is run, the tab stops of the terminal should be - set and its initialization strings, if defined, must be output. This - can be done by executing the tput init command after the shell environ- - ment variable TERM has been exported. tset(1) is usually responsible - for doing this. [See terminfo(5) for further details.] - - -
- The ncurses library permits manipulation of data structures, called - windows, which can be thought of as two-dimensional arrays of charac- - ters representing all or part of a CRT screen. A default window called - stdscr, which is the size of the terminal screen, is supplied. Others - may be created with newwin. - - Note that curses does not handle overlapping windows, that's done by - the panel(3x) library. This means that you can either use stdscr or - divide the screen into tiled windows and not using stdscr at all. Mix- - ing the two will result in unpredictable, and undesired, effects. - - Windows are referred to by variables declared as WINDOW *. These data - structures are manipulated with routines described here and elsewhere - in the ncurses manual pages. Among those, the most basic routines are - move and addch. More general versions of these routines are included - with names beginning with w, allowing the user to specify a window. - The routines not beginning with w affect stdscr. - - After using routines to manipulate a window, refresh(3x) is called, - telling curses to make the user's CRT screen look like stdscr. The - characters in a window are actually of type chtype, (character and - attribute data) so that other information about the character may also - be stored with each character. - - Special windows called pads may also be manipulated. These are windows - which are not constrained to the size of the screen and whose contents - need not be completely displayed. See curs_pad(3x) for more informa- - tion. - - In addition to drawing characters on the screen, video attributes and - colors may be supported, causing the characters to show up in such - modes as underlined, in reverse video, or in color on terminals that - support such display enhancements. Line drawing characters may be - specified to be output. On input, curses is also able to translate - arrow and function keys that transmit escape sequences into single val- - ues. The video attributes, line drawing characters, and input values - use names, defined in <curses.h>, such as A_REVERSE, ACS_HLINE, and - KEY_LEFT. - - -
- If the environment variables LINES and COLUMNS are set, or if the pro- - gram is executing in a window environment, line and column information - in the environment will override information read by terminfo. This - would affect a program running in an AT&T 630 layer, for example, where - the size of a screen is changeable (see ENVIRONMENT). - - If the environment variable TERMINFO is defined, any program using - curses checks for a local terminal definition before checking in the - standard place. For example, if TERM is set to att4424, then the com- - piled terminal definition is found in - - /usr/share/terminfo/a/att4424. - - (The a is copied from the first letter of att4424 to avoid creation of - huge directories.) However, if TERMINFO is set to $HOME/myterms, - curses first checks - - $HOME/myterms/a/att4424, - - and if that fails, it then checks - - /usr/share/terminfo/a/att4424. - - This is useful for developing experimental definitions or when write - permission in /usr/share/terminfo is not available. - - The integer variables LINES and COLS are defined in <curses.h> and will - be filled in by initscr with the size of the screen. The constants - TRUE and FALSE have the values 1 and 0, respectively. - - The curses routines also define the WINDOW * variable curscr which is - used for certain low-level operations like clearing and redrawing a - screen containing garbage. The curscr can be used in only a few rou- - tines. - - -
- Many curses routines have two or more versions. The routines prefixed - with w require a window argument. The routines prefixed with p require - a pad argument. Those without a prefix generally use stdscr. - - The routines prefixed with mv require a y and x coordinate to move to - before performing the appropriate action. The mv routines imply a call - to move before the call to the other routine. The coordinate y always - refers to the row (of the window), and x always refers to the column. - The upper left-hand corner is always (0,0), not (1,1). - - The routines prefixed with mvw take both a window argument and x and y - coordinates. The window argument is always specified before the coor- - dinates. - - In each case, win is the window affected, and pad is the pad affected; - win and pad are always pointers to type WINDOW. - - Option setting routines require a Boolean flag bf with the value TRUE - or FALSE; bf is always of type bool. Most of the data types used in - the library routines, such as WINDOW, SCREEN, bool, and chtype are - defined in <curses.h>. Types used for the terminfo routines such as - TERMINAL are defined in <term.h>. - - This manual page describes functions which may appear in any configura- - tion of the library. There are two common configurations of the - library: - - ncurses - the "normal" library, which handles 8-bit characters. The nor- - mal (8-bit) library stores characters combined with attributes - in chtype data. - - Attributes alone (no corresponding character) may be stored in - chtype or the equivalent attr_t data. In either case, the data - is stored in something like an integer. - - Each cell (row and column) in a WINDOW is stored as a chtype. - - ncursesw - the so-called "wide" library, which handles multibyte charac- - ters (see the section on ALTERNATE CONFIGURATIONS). The "wide" - library includes all of the calls from the "normal" library. - It adds about one third more calls using data types which store - multibyte characters: - - cchar_t - corresponds to chtype. However it is a structure, because - more data is stored than can fit into an integer. The - characters are large enough to require a full integer - value - and there may be more than one character per cell. - The video attributes and color are stored in separate - fields of the structure. - - Each cell (row and column) in a WINDOW is stored as a - cchar_t. - - wchar_t - stores a "wide" character. Like chtype, this may be an - integer. - - wint_t - stores a wchar_t or WEOF - not the same, though both may - have the same size. - - The "wide" library provides new functions which are analogous - to functions in the "normal" library. There is a naming con- - vention which relates many of the normal/wide variants: a "_w" - is inserted into the name. For example, waddch becomes - wadd_wch. - - -
- The following table lists each curses routine and the name of the man- - ual page on which it is described. Routines flagged with "*" are - ncurses-specific, not described by XPG4 or present in SVr4. - - curses Routine Name Manual Page Name + The selection of an appropriate value of TERM in the process + environment is essential to correct curses and terminfo library + operation. A well-configured system selects a correct TERM value + automatically; tset(1) may assist with troubleshooting exotic + situations. + + If you change the terminal type, export the shell's TERM variable, then + run tset(1) or the "tput init" command. See subsection "Tabs and + Initialization" of terminfo(5). + + If the environment variables LINES and COLUMNS are set, or if the + curses program is executing in a graphical windowing environment, the + information obtained thence overrides that obtained by terminfo. An + ncurses extension supports resizable terminals; see wresize(3x). + + If the environment variable TERMINFO is defined, a curses program + checks first for a terminal type description in the location it + identifies. TERMINFO is useful for developing type descriptions or + when write permission to /usr/share/terminfo is not available. + + See section "ENVIRONMENT" below. + + +
+ curses offers many functions in variant forms using a regular set of + alternatives to the name of an elemental one. Those prefixed with "w" + require a WINDOW pointer argument; those with a "mv" prefix first + perform cursor movement using wmove(3x); a "mvw" prefix indicates both. + The "w" function is typically the elemental one; the removal of this + prefix usually indicates operation on stdscr. + + Four functions prefixed with "p" require a pad argument. + + In function synopses, ncurses man pages apply the following names to + parameters. + + bf a bool (TRUE or FALSE) + c a char or int + ch a chtype + wc a wchar_t or wint_t + wch a cchar_t + win pointer to a WINDOW + pad pointer to a WINDOW that is a pad + + +
+ This man page primarily surveys functions that appear in any + configuration of the library. There are two common configurations; see + section "ALTERNATE CONFIGURATIONS" below. + + ncurses is the library in its "non-wide" configuration, handling only + eight-bit characters. It stores a character combined with + attributes and a color pair in a chtype datum, which is often + an alias of int. A string of curses characters is similar to + a C char string; a chtype string ends with an integral 0, the + null curses character. + + Attributes and a color pair selection (with no corresponding + character) can be stored in variables of chtype or attr_t + type. In either case, they are accessed via an integral bit + mask. + + Each cell of a WINDOW is stored as a chtype. + + ncursesw is the library in its "wide" configuration, which handles + character encodings requiring a larger data type than char (a + byte-sized type) can represent. It adds about one third more + calls using additional data types that can store such + multibyte characters. + + cchar_t corresponds to the non-wide configuration's chtype. + It always a structure type, because it stores more + data than fit into a standard scalar type. A + character code may not be representable as a char, + and moreover more than one character may occupy a + cell (as with accent marks and other diacritics). + Each character is of type wchar_t; a complex + character contains one spacing character and zero or + more non-spacing characters (see below). A string + of complex characters ends with a cchar_t whose + wchar_t member is the null wide character. + Attributes and a color pair selection are stored in + separate fields of the structure, not combined into + an integer as in chtype. + + Each cell of a WINDOW is stored as a cchar_t. + + setcchar(3x) and getcchar(3x) store and retrieve cchar_t + data. The wide library API of ncurses depends on two data + types standardized by ISO C95. + + wchar_t stores a wide character. Like chtype, it may be an + alias of int. Depending on the character encoding, + a wide character may be spacing, meaning that it + occupies a character cell by itself and typically + accompanies cursor advancement, or non-spacing, + meaning that it occupies the same cell as a spacing + character, is often regarded as a "modifier" of the + base glyph with which it combines, and typically + does not advance the cursor. + + wint_t can store a wchar_t or the constant WEOF, + analogously to the int-sized character manipulation + functions of ISO C and its constant EOF. + + The wide library provides additional functions that + complement those in the non-wide library where the size of + the underlying character type is significant. A somewhat + regular naming convention relates many of the wide variants + to their non-wide counterparts; where a non-wide function + name contains "ch" or "str", prefix it with "_w" to obtain + the wide counterpart. For example, waddch becomes wadd_wch. + (Exceptions that add only "w" comprise addwstr, inwstr, and + their variants.) + + This convention is inapplicable to some non-wide function + names, so other transformations are used for the wide + configuration: the window background management function + "bkgd" becomes "bkgrnd"; the window border-drawing and + -clearing functions are suffixed with "_set"; and character + attribute manipulation functions like "attron" become + "attr_on". + + +
+ The following table lists the curses functions provided in the non-wide + and wide APIs and the corresponding man pages that describe them. + Those flagged with "*" are ncurses-specific, neither described by + X/Open Curses nor present in SVr4. + + curses Function Name Man Page --------------------------------------------- COLOR_PAIR curs_color(3x) - PAIR_NUMBER curs_attr(3x) - _nc_free_and_exit curs_memleaks(3x)* - _nc_freeall curs_memleaks(3x)* - _nc_tracebits curs_trace(3x)* - _traceattr curs_trace(3x)* - _traceattr2 curs_trace(3x)* - _tracechar curs_trace(3x)* - _tracechtype curs_trace(3x)* - _tracechtype2 curs_trace(3x)* - _tracedump curs_trace(3x)* - _tracef curs_trace(3x)* - _tracemouse curs_trace(3x)* + PAIR_NUMBER curs_color(3x) add_wch curs_add_wch(3x) add_wchnstr curs_add_wchstr(3x) add_wchstr curs_add_wchstr(3x) @@ -312,7 +351,6 @@ attroff curs_attr(3x) attron curs_attr(3x) attrset curs_attr(3x) - baudrate curs_termattrs(3x) beep curs_beep(3x) bkgd curs_bkgd(3x) @@ -334,6 +372,7 @@ color_set curs_attr(3x) copywin curs_overlay(3x) curs_set curs_kernel(3x) + curses_trace curs_trace(3x)* curses_version curs_extend(3x)* def_prog_mode curs_kernel(3x) def_shell_mode curs_kernel(3x) @@ -343,6 +382,7 @@ delch curs_delch(3x) deleteln curs_deleteln(3x) delscreen curs_initscr(3x) + delwin curs_window(3x) derwin curs_window(3x) doupdate curs_refresh(3x) @@ -354,6 +394,8 @@ erase curs_clear(3x) erasechar curs_termattrs(3x) erasewchar curs_termattrs(3x) + exit_curses curs_memleaks(3x)* + exit_terminfo curs_memleaks(3x)* extended_color_content curs_color(3x)* extended_pair_content curs_color(3x)* extended_slk_color curs_slk(3x)* @@ -362,6 +404,7 @@ flash curs_beep(3x) flushinp curs_util(3x) free_pair new_pair(3x)* + get_escdelay curs_threads(3x)* get_wch curs_get_wch(3x) get_wstr curs_get_wstr(3x) getattrs curs_attr(3x) @@ -378,7 +421,6 @@ getmaxy curs_legacy(3x)* getmaxyx curs_getyx(3x) getmouse curs_mouse(3x)* - getn_wstr curs_get_wstr(3x) getnstr curs_getstr(3x) getparx curs_legacy(3x)* @@ -393,6 +435,7 @@ has_ic curs_termattrs(3x) has_il curs_termattrs(3x) has_key curs_getch(3x)* + has_mouse curs_mouse(3x)* hline curs_border(3x) hline_set curs_border_set(3x) idcok curs_outopts(3x) @@ -406,6 +449,7 @@ inchstr curs_inchstr(3x) init_color curs_color(3x) init_extended_color curs_color(3x)* + init_extended_pair curs_color(3x)* init_pair curs_color(3x) initscr curs_initscr(3x) @@ -422,16 +466,20 @@ instr curs_instr(3x) intrflush curs_inopts(3x) inwstr curs_inwstr(3x) + is_cbreak curs_inopts(3x)* is_cleared curs_opaque(3x)* + is_echo curs_inopts(3x)* is_idcok curs_opaque(3x)* is_idlok curs_opaque(3x)* is_immedok curs_opaque(3x)* is_keypad curs_opaque(3x)* is_leaveok curs_opaque(3x)* is_linetouched curs_touch(3x) + is_nl curs_inopts(3x)* is_nodelay curs_opaque(3x)* is_notimeout curs_opaque(3x)* is_pad curs_opaque(3x)* + is_raw curs_inopts(3x)* is_scrollok curs_opaque(3x)* is_subwin curs_opaque(3x)* is_syncok curs_opaque(3x)* @@ -444,7 +492,6 @@ keyname curs_util(3x) keyok keyok(3x)* keypad curs_inopts(3x) - killchar curs_termattrs(3x) killwchar curs_termattrs(3x) leaveok curs_outopts(3x) @@ -469,6 +516,7 @@ mvcur curs_terminfo(3x) mvdelch curs_delch(3x) mvderwin curs_window(3x) + mvget_wch curs_get_wch(3x) mvget_wstr curs_get_wstr(3x) mvgetch curs_getch(3x) @@ -510,7 +558,6 @@ mvwchgat curs_attr(3x) mvwdelch curs_delch(3x) mvwget_wch curs_get_wch(3x) - mvwget_wstr curs_get_wstr(3x) mvwgetch curs_getch(3x) mvwgetn_wstr curs_get_wstr(3x) @@ -536,6 +583,7 @@ mvwinstr curs_instr(3x) mvwinwstr curs_inwstr(3x) mvwprintw curs_printw(3x) + mvwscanw curs_scanw(3x) mvwvline curs_border(3x) mvwvline_set curs_border_set(3x) @@ -543,18 +591,19 @@ newpad curs_pad(3x) newterm curs_initscr(3x) newwin curs_window(3x) - nl curs_outopts(3x) + nl curs_inopts(3x) nocbreak curs_inopts(3x) nodelay curs_inopts(3x) noecho curs_inopts(3x) nofilter curs_util(3x)* - nonl curs_outopts(3x) + nonl curs_inopts(3x) noqiflush curs_inopts(3x) noraw curs_inopts(3x) notimeout curs_inopts(3x) overlay curs_overlay(3x) overwrite curs_overlay(3x) pair_content curs_color(3x) + pecho_wchar curs_pad(3x) pechochar curs_pad(3x) pnoutrefresh curs_pad(3x) prefresh curs_pad(3x) @@ -565,6 +614,7 @@ raw curs_inopts(3x) redrawwin curs_refresh(3x) refresh curs_refresh(3x) + reset_color_pairs curs_color(3x)* reset_prog_mode curs_kernel(3x) reset_shell_mode curs_kernel(3x) resetty curs_kernel(3x) @@ -576,18 +626,18 @@ scanw curs_scanw(3x) scr_dump curs_scr_dump(3x) scr_init curs_scr_dump(3x) - scr_restore curs_scr_dump(3x) scr_set curs_scr_dump(3x) scrl curs_scroll(3x) scroll curs_scroll(3x) scrollok curs_outopts(3x) set_curterm curs_terminfo(3x) + set_escdelay curs_threads(3x)* + set_tabsize curs_threads(3x)* set_term curs_initscr(3x) setcchar curs_getcchar(3x) setscrreg curs_outopts(3x) setsyx curs_kernel(3x) - setterm curs_terminfo(3x) setupterm curs_terminfo(3x) slk_attr curs_slk(3x)* slk_attr_off curs_slk(3x) @@ -600,11 +650,13 @@ slk_color curs_slk(3x) slk_init curs_slk(3x) slk_label curs_slk(3x) + slk_noutrefresh curs_slk(3x) slk_refresh curs_slk(3x) slk_restore curs_slk(3x) slk_set curs_slk(3x) slk_touch curs_slk(3x) + slk_wset curs_slk(3x) standend curs_attr(3x) standout curs_attr(3x) start_color curs_color(3x) @@ -623,7 +675,9 @@ tigetnum curs_terminfo(3x) tigetstr curs_terminfo(3x) timeout curs_inopts(3x) - tiparm curs_terminfo(3x)* + tiparm curs_terminfo(3x) + tiparm_s curs_terminfo(3x)* + tiscan_s curs_terminfo(3x)* touchline curs_touch(3x) touchwin curs_touch(3x) tparm curs_terminfo(3x) @@ -640,9 +694,10 @@ use_env curs_util(3x) use_extended_names curs_extend(3x)* use_legacy_coding legacy_coding(3x)* - use_tioctl curs_util(3x) + use_screen curs_threads(3x)* + use_tioctl curs_util(3x)* + use_window curs_threads(3x)* vid_attr curs_terminfo(3x) - vid_puts curs_terminfo(3x) vidattr curs_terminfo(3x) vidputs curs_terminfo(3x) @@ -662,6 +717,7 @@ waddnwstr curs_addwstr(3x) waddstr curs_addstr(3x) waddwstr curs_addwstr(3x) + wattr_get curs_attr(3x) wattr_off curs_attr(3x) wattr_on curs_attr(3x) @@ -708,7 +764,6 @@ winnstr curs_instr(3x) winnwstr curs_inwstr(3x) wins_nwstr curs_ins_wstr(3x) - wins_wch curs_ins_wch(3x) wins_wstr curs_ins_wstr(3x) winsch curs_insch(3x) @@ -729,6 +784,7 @@ wscrl curs_scroll(3x) wsetscrreg curs_outopts(3x) wstandend curs_attr(3x) + wstandout curs_attr(3x) wsyncdown curs_window(3x) wsyncup curs_window(3x) @@ -738,583 +794,702 @@ wvline curs_border(3x) wvline_set curs_border_set(3x) + ncurses's screen-pointer extension adds additional functions + corresponding to many of the above, each with an "_sp" suffix; see + curs_sp_funcs(3x). -
- Routines that return an integer return ERR upon failure and an integer - value other than ERR upon successful completion, unless otherwise noted - in the routine descriptions. - - As a general rule, routines check for null pointers passed as parame- - ters, and handle this as an error. + The availability of some extensions is configurable when ncurses is + compiled; see sections "ALTERNATE CONFIGURATIONS" and "EXTENSIONS" + below. - All macros return the value of the w version, except setscrreg, - wsetscrreg, getyx, getbegyx, and getmaxyx. The return values of - setscrreg, wsetscrreg, getyx, getbegyx, and getmaxyx are undefined - (i.e., these should not be used as the right-hand side of assignment - statements). - Routines that return pointers return NULL on error. +
+ Unless otherwise noted, functions that return integers return the + constants OK on success and ERR on failure; see curs_variables(3x). + Functions that return pointers return NULL on failure. Typically, + ncurses treats a null pointer passed as a function parameter as a + failure. Functions prefixed with "mv" first perform cursor movement + and fail if the position (y, x) is outside the window boundaries.
- The following environment symbols are useful for customizing the run- - time behavior of the ncurses library. The most important ones have - been already discussed in detail. + The following symbols from the process environment customize the + runtime behavior of ncurses applications. The library may be + configured to disregard the variables TERMINFO, TERMINFO_DIRS, + TERMPATH, and HOME, if the user is the superuser (root), or the + application uses setuid(2) or setgid(2). + +
+ The debugging library checks this variable when the application has + redirected output to a file. Its integral value is used for the baud + rate. If that value is absent or invalid, ncurses uses 9600. This + feature allows developers to construct repeatable test cases that take + into account optimization decisions that depend on baud rate. -
- When set, change occurrences of the command_character (i.e., the cmdch - capability) of the loaded terminfo entries to the value of this vari- - able. Very few terminfo entries provide this feature. + +
+ When set, the command_character (cmdch) capability value of loaded + terminfo entries changes to the value of this variable. Very few term- + info entries provide this feature. Because this name is also used in development environments to represent - the C compiler's name, ncurses ignores it if it does not happen to be a - single character. + the C compiler's name, ncurses ignores its value if it is not one + character in length. + + +
+ This variable specifies the width of the screen in characters. + Applications running in a windowing environment usually are able to + obtain the width of the window in which they are executing. If COLUMNS + is not defined and the terminal's screen size is not available from the + terminal driver, ncurses uses the size specified by the columns (cols) + capability of the terminal type's entry in the terminfo database, if + any. + + It is important that your application use the correct screen size. + Automatic detection thereof is not always possible because an + application may be running on a host that does not honor NAWS + (Negotiations About Window Size) or as a different user ID than the + owner of the terminal device file. Setting COLUMNS and/or LINES + overrides the library's use of the screen size obtained from the + operating system. + + The COLUMNS and LINES variables may be specified independently. + ncurses enforces an upper limit of 512 on each when reading the value. + This property is useful to circumvent misfeatures of legacy terminal + type descriptions; xterm(1) descriptions specifying 65 lines were once + notorious. For best results, avoid specifying cols and lines + capability codes in terminfo descriptions of terminal emulators. + + use_env(3x) can disable use of the process environment in determining + the screen size. use_tioctl(3x) can update COLUMNS and LINES to match + the screen size obtained from system calls or the terminal database. + + +
+ For curses to distinguish the ESC character resulting from a user's + press of the "Escape" key on the input device from one beginning an + escape sequence (as commonly produced by function keys), it waits after + receiving the escape character to see if further characters are + available on the input stream within a short interval. A global + variable ESCDELAY stores this interval in milliseconds. The default + value of 1000 (one second) is adequate for most uses. This environment + variable overrides it; ncurses enforces an upper limit of 30,000 (30 + seconds) when reading the value. + + The most common instance where you may wish to change this value is to + work with a remote host over a slow communication channel. If the host + running a curses application does not receive the characters of an + escape sequence in a timely manner, the library can interpret them as + multiple key stroke events. + + xterm(1) mouse events are a form of escape sequence; therefore, if your + application makes heavy use of multiple-clicking, you may wish to + lengthen the default value because the delay applies to the composite + multi-click event as well as the individual clicks. + + Portable applications should not rely upon the presence of ESCDELAY in + either form, but setting the environment variable rather than the + global variable does not create problems when compiling an application. + + If keypad(3x) is disabled for the curses window receiving input, a + program must disambiguate escape sequences itself. + + +
+ ncurses may read and write auxiliary terminal descriptions in .termcap + and .terminfo files in the user's home directory. + + +
+ This counterpart to COLUMNS specifies the height of the screen in + characters. The corresponding terminfo capability and code is lines. + See the description of the COLUMNS variable above. + + +
+ (OS/2 EMX port only) OS/2 numbers a three-button mouse inconsistently + with other platforms, such that 1 is the left button, 2 the right, and + 3 the middle. This variable customizes the mouse button numbering. + Its value must be three digits 1-3 in any order. By default, ncurses + assumes a numbering of "132". + + +
+ If set, this variable overrides the ncurses library's compiled-in + assumption that the terminal's default colors are white on black; see + default_colors(3x). Set the foreground and background color values + with this environment variable by assigning it two integer values + separated by a comma, indicating foregound and background color + numbers, respectively. + + For example, to tell ncurses not to assume anything about the colors, + use a value of "-1,-1". To make the default color scheme green on + black, use "2,0". ncurses accepts integral values from -1 up to the + value of the terminfo max_colors (colors) capability. + + +
+ (MinGW port only) The Console2 program defectively handles the + Microsoft Console API call CreateConsoleScreenBuffer. Applications + that use it will hang. However, it is possible to simulate the action + of this call by mapping coordinates, explicitly saving and restoring + the original screen contents. Setting the environment variable NCGDB + has the same effect. + + +
+ (Linux only) When ncurses is configured to use the GPM interface, this + variable may list one or more terminal type names, delimited by + vertical bars (|) or colons (:), against which the TERM variable (see + below) is matched. An empty value disables the GPM interface, using + ncurses's built-in support for xterm(1) mouse protocols instead. If + the variable is absent, ncurses attempts to open GPM if TERM contains + "linux". + + +
+ ncurses may use tab characters in cursor movement optimization. In + some cases, your terminal driver may not handle them properly. Set + this environment variable to any value to disable the feature. You can + also adjust your stty(1) settings to avoid the problem. + + +
+ Many terminals store video attributes as a property of a character + cell, as curses does. Historically, some recorded changes in video + attributes as data that logically occupies character cells on the + display, switching attributes on or off, similarly to tags in a markup + language; these are termed "magic cookies", and must be subsequently + overprinted. If the terminfo entry for your terminal type does not + adequately describe its handling of magic cookies, set this variable to + any value to instruct ncurses to disable attributes entirely. + + +
+ Most terminal type descriptions in the terminfo database detail + hardware devices. Many people use curses-based applications in + terminal emulator programs that run in a windowing environment. These + programs can duplicate all of the important features of a hardware + terminal, but often lack their limitations. Chief among these absent + drawbacks is the problem of data flow management; that is, limiting the + speed of communication to what the hardware could handle. Unless a + hardware terminal is interfaced into a terminal concentrator (which + does flow control), an application must manage flow itself to prevent + overruns and data loss. + + A solution that comes at no hardware cost is for an application to + pause after directing a terminal to execute an operation that it + performs slowly, such as clearing the display. Many terminal type + descriptions, including that for the VT100, embed delay specifications + in capabilities. You may wish to use these terminal descriptions + without paying the performance penalty. Set NCURSES_NO_PADDING to any + value to disable all but mandatory padding. Mandatory padding is used + by such terminal capabilities as flash_screen (flash). + + +
+ (Obsolete) Prior to internal changes developed in ncurses 5.9 (patches + 20120825 through 20130126), the library used setbuf(3) to enable fully + buffered output when initializing the terminal. This was done, as in + SVr4 curses, to increase performance. For testing purposes, both of + ncurses and of certain applications, this feature was made optional. + Setting this variable disabled output buffering, leaving the output + stream in the original (usually line-buffered) mode. + + Nowadays, ncurses performs its own buffering and does not require this + workaround; it does not modify the buffering of the standard output + stream. This approach makes signal handling, as for interrupts, more + robust. A drawback is that certain unconventional programs mixed + stdio(3) calls with ncurses calls and (usually) got the behavior they + expected. This is no longer the case; ncurses does not write to the + standard output file descriptor through a stdio-buffered stream. + + As a special case, low-level API calls such as putp(3x) still use the + standard output stream. High-level curses calls such as printw(3x) do + not. + + +
+ At initialization, ncurses inspects the TERM environment variable for + special cases where VT100 forms-drawing characters (and the + corresponding alternate character set terminfo capabilities) are known + to be unsupported by terminal types that otherwise claim VT100 + compatibility. Specifically, when running in a UTF-8 locale, the Linux + virtual console device and the GNU screen(1) program ignore them. Set + this variable to a nonzero value to instruct ncurses that the + terminal's ACS support is broken; the library then outputs Unicode code + points that correspond to the forms-drawing characters. Set it to zero + (or a non-integer) to disable the special check for terminal type names + matching "linux" or "screen", directing ncurses to assume that the ACS + feature works if the terminal type description advertises it. + + As an alternative to use of this variable, ncurses checks for an + extended terminfo numeric capability U8 that can be compiled using "tic + -x". Examples follow. + # linux console, if patched to provide working + # VT100 shift-in/shift-out, with corresponding font. + linux-vt100|linux console with VT100 line-graphics, + U8#0, use=linux, -
- The debugging library checks this environment variable when the appli- - cation has redirected output to a file. The variable's numeric value - is used for the baudrate. If no value is found, ncurses uses 9600. - This allows testers to construct repeatable test-cases that take into - account costs that depend on baudrate. + # uxterm with vt100Graphics resource set to false + xterm-utf8|xterm relying on UTF-8 line-graphics, + U8#1, use=xterm, + The two-character name "U8" was chosen to permit its use via ncurses's + termcap interface. -
- Specify the width of the screen in characters. Applications running in - a windowing environment usually are able to obtain the width of the - window in which they are executing. If neither the COLUMNS value nor - the terminal's screen size is available, ncurses uses the size which - may be specified in the terminfo database (i.e., the cols capability). - It is important that your application use a correct size for the - screen. This is not always possible because your application may be - running on a host which does not honor NAWS (Negotiations About Window - Size), or because you are temporarily running as another user. How- - ever, setting COLUMNS and/or LINES overrides the library's use of the - screen size obtained from the operating system. +
+ At initialization, ncurses (in its debugging configuration) checks for + this variable's presence. If defined with an integral value, the + library calls curses_trace(3x) with that value as the argument. - Either COLUMNS or LINES symbols may be specified independently. This - is mainly useful to circumvent legacy misfeatures of terminal descrip- - tions, e.g., xterm which commonly specifies a 65 line screen. For best - results, lines and cols should not be specified in a terminal descrip- - tion for terminals which are run as emulations. - Use the use_env function to disable all use of external environment - (but not including system calls) to determine the screen size. Use the - use_tioctl function to update COLUMNS or LINES to match the screen size - obtained from system calls or the terminal database. +
+ The TERM variable denotes the terminal type. Each is distinct, though + many are similar. It is commonly set by terminal emulators to help + applications find a workable terminal description. Some choose a + popular approximation such as "ansi", "vt100", or "xterm" rather than + an exact fit to their capabilities. Not infrequently, an application + will have problems with that approach; for example, a key stroke may + not operate correctly, or produce no effect but seeming garbage + characters on the screen. + Setting TERM has no effect on hardware operation; it affects the way + applications communicate with the terminal. Likewise, as a general + rule (xterm(1) being a rare exception), terminal emulators that allow + you to specify TERM as a parameter or configuration value do not change + their behavior to match that setting. -
- Specifies the total time, in milliseconds, for which ncurses will await - a character sequence, e.g., a function key. The default value, 1000 - milliseconds, is enough for most uses. However, it is made a variable - to accommodate unusual applications. - The most common instance where you may wish to change this value is to - work with slow hosts, e.g., running on a network. If the host cannot - read characters rapidly enough, it will have the same effect as if the - terminal did not send characters rapidly enough. The library will - still see a timeout. +
+ If ncurses is configured with termcap support, it checks for a terminal + type description in termcap format if one in terminfo format is not + available. Setting this variable directs ncurses to ignore the usual + termcap database location, /etc/termcap; see TERMPATH below. TERMCAP + should contain either a terminal description (with newlines stripped + out), or a file name indicating where the information required by the + TERM environment variable is stored. - Note that xterm mouse events are built up from character sequences - received from the xterm. If your application makes heavy use of multi- - ple-clicking, you may wish to lengthen this default value because the - timeout applies to the composed multi-click event as well as the indi- - vidual clicks. - In addition to the environment variable, this implementation provides a - global variable with the same name. Portable applications should not - rely upon the presence of ESCDELAY in either form, but setting the - environment variable rather than the global variable does not create - problems when compiling an application. +
+ ncurses can be configured to read terminal type description databases + in various locations using different formats. This variable overrides + the default location. + o Descriptions in terminfo format are normally stored in a directory + tree using subdirectories named by the common first letters of the + terminal types named therein. This is the scheme used in System V. -
- Tells ncurses where your home directory is. That is where it may read - and write auxiliary terminal descriptions: + o If ncurses is configured to use hashed databases, then TERMINFO may + name its location, such as /usr/share/terminfo.db, rather than + /usr/share/terminfo/. - $HOME/.termcap - $HOME/.terminfo + The hashed database uses less disk space and is a little faster than + the directory tree. However, some applications assume the existence of + the directory tree, and read it directly rather than using the terminfo + API. + o If ncurses is configured with termcap support, this variable may + contain the location of a termcap file. -
- Like COLUMNS, specify the height of the screen in characters. See COL- - UMNS for a detailed description. + o If the value of TERMINFO begins with "hex:" or "b64:", ncurses uses + the remainder of the value as a compiled terminfo description. You + might produce the base64 format using infocmp(1m). + TERMINFO=$(infocmp -0 -Q2 -q) + export TERMINFO -
- This applies only to the OS/2 EMX port. It specifies the order of but- - tons on the mouse. OS/2 numbers a 3-button mouse inconsistently from - other platforms: + The compiled description is used only if it corresponds to the + terminal type identified by TERM. - 1 = left - 2 = right - 3 = middle. + Setting TERMINFO is the simplest, but not the only, way to direct + ncurses to a terminal database. The search path is as follows. - This variable lets you customize the mouse. The variable must be three - numeric digits 1-3 in any order, e.g., 123 or 321. If it is not speci- - fied, ncurses uses 132. + o the last terminal database to which the running ncurses application + wrote, if any + o the location specified by the TERMINFO environment variable -
- Override the compiled-in assumption that the terminal's default colors - are white-on-black (see default_colors(3x)). You may set the fore- - ground and background color values with this environment variable by - proving a 2-element list: foreground,background. For example, to tell - ncurses to not assume anything about the colors, set this to "-1,-1". - To make it green-on-black, set it to "2,0". Any positive value from - zero to the terminfo max_colors value is allowed. + o $HOME/.terminfo + o locations listed in the TERMINFO_DIRS environment variable -
- This applies only to the MinGW port of ncurses. + o location(s) configured and compiled into ncurses - The Console2 program's handling of the Microsoft Console API call Cre- - ateConsoleScreenBuffer is defective. Applications which use this will - hang. However, it is possible to simulate the action of this call by - mapping coordinates, explicitly saving and restoring the original - screen contents. Setting the environment variable NCGDB has the same - effect. + o /usr/share/terminfo -
- This applies only to ncurses configured to use the GPM interface. - - If present, the environment variable is a list of one or more terminal - names against which the TERM environment variable is matched. Setting - it to an empty value disables the GPM interface; using the built-in - support for xterm, etc. +
+ This variable specifies a list of locations, akin to PATH, in which + ncurses searches for the terminal type descriptions described by + TERMINFO above. The list items are separated by colons on Unix and + semicolons on OS/2 EMX. System V terminfo lacks a corresponding + feature; TERMINFO_DIRS is an ncurses extension. - If the environment variable is absent, ncurses will attempt to open GPM - if TERM contains "linux". +
+ If TERMCAP does not hold a terminal type description or file name, then + ncurses checks the contents of TERMPATH, a list of locations, akin to + PATH, in which it searches for termcap terminal type descriptions. The + list items are separated by colons on Unix and semicolons on OS/2 EMX. -
- Ncurses may use tabs as part of the cursor movement optimization. In - some cases, your terminal driver may not handle these properly. Set - this environment variable to disable the feature. You can also adjust - your stty settings to avoid the problem. + If both TERMCAP and TERMPATH are unset or invalid, ncurses searches for + the files /etc/termcap, /usr/share/misc/termcap, and $HOME/.termcap, in + that order. -
- Some terminals use a magic-cookie feature which requires special han- - dling to make highlighting and other video attributes display properly. - You can suppress the highlighting entirely for these terminals by set- - ting this environment variable. +
+ Many different ncurses configurations are possible, determined by the + options given to the configure script when building the library. Run + the script with the --help option to peruse them all. A few are of + particular significance to the application developer employing ncurses. + --disable-overwrite + The standard C preprocessor inclusion for the curses library is as + follows. -
- Most of the terminal descriptions in the terminfo database are written - for real "hardware" terminals. Many people use terminal emulators - which run in a windowing environment and use curses-based applications. - Terminal emulators can duplicate all of the important aspects of a - hardware terminal, but they do not have the same limitations. The - chief limitation of a hardware terminal from the standpoint of your - application is the management of dataflow, i.e., timing. Unless a - hardware terminal is interfaced into a terminal concentrator (which - does flow control), it (or your application) must manage dataflow, pre- - venting overruns. The cheapest solution (no hardware cost) is for your - program to do this by pausing after operations that the terminal does - slowly, such as clearing the display. - - As a result, many terminal descriptions (including the vt100) have - delay times embedded. You may wish to use these descriptions, but not - want to pay the performance penalty. - - Set the NCURSES_NO_PADDING environment variable to disable all but - mandatory padding. Mandatory padding is used as a part of special con- - trol sequences such as flash. - - -
- This setting is obsolete. Before changes - - o started with 5.9 patch 20120825 and - - o continued though 5.9 patch 20130126 - - ncurses enabled buffered output during terminal initialization. This - was done (as in SVr4 curses) for performance reasons. For testing pur- - poses, both of ncurses and certain applications, this feature was made - optional. Setting the NCURSES_NO_SETBUF variable disabled output - buffering, leaving the output in the original (usually line buffered) - mode. - - In the current implementation, ncurses performs its own buffering and - does not require this workaround. It does not modify the buffering of - the standard output. - - The reason for the change was to make the behavior for interrupts and - other signals more robust. One drawback is that certain nonconven- - tional programs would mix ordinary stdio calls with ncurses calls and - (usually) work. This is no longer possible since ncurses is not using - the buffered standard output but its own output (to the same file - descriptor). As a special case, the low-level calls such as putp still - use the standard output. But high-level curses calls do not. - - -
- During initialization, the ncurses library checks for special cases - where VT100 line-drawing (and the corresponding alternate character set - capabilities) described in the terminfo are known to be missing. - Specifically, when running in a UTF-8 locale, the Linux console emula- - tor and the GNU screen program ignore these. Ncurses checks the TERM - environment variable for these. For other special cases, you should - set this environment variable. Doing this tells ncurses to use Unicode - values which correspond to the VT100 line-drawing glyphs. That works - for the special cases cited, and is likely to work for terminal emula- - tors. - - When setting this variable, you should set it to a nonzero value. Set- - ting it to zero (or to a nonnumber) disables the special check for - "linux" and "screen". - - As an alternative to the environment variable, ncurses checks for an - extended terminfo capability U8. This is a numeric capability which - can be compiled using tic -x. For example + #include <curses.h> - # linux console, if patched to provide working - # VT100 shift-in/shift-out, with corresponding font. - linux-vt100|linux console with VT100 line-graphics, - U8#0, use=linux, + This option is used to avoid file name conflicts between ncurses + and an existing curses installation on the system. If ncurses is + installed disabling overwrite, it puts its header files in a + subdirectory. Here is an example. - # uxterm with vt100Graphics resource set to false - xterm-utf8|xterm relying on UTF-8 line-graphics, - U8#1, use=xterm, + #include <ncurses/curses.h> - The name "U8" is chosen to be two characters, to permit it to be used - by applications that use ncurses' termcap interface. + Installation also omits a symbolic link that would cause the + compiler's -lcurses option to link object files with ncurses + instead of the system curses library. + The directory used by this configuration of ncurses is shown in + section "SYNOPSIS" above. -
- During initialization, the ncurses debugging library checks the - NCURSES_TRACE environment variable. If it is defined, to a numeric - value, ncurses calls the trace function, using that value as the argu- - ment. + --enable-widec + The configure script renames the library and (if the + --disable-overwrite option is used) puts the header files in a + different subdirectory. All of the library names have a "w" + appended to them, i.e., instead of - The argument values, which are defined in curses.h, provide several - types of information. When running with traces enabled, your applica- - tion will write the file trace to the current directory. + -lncurses - See curs_trace(3x) for more information. + you link with + -lncursesw -
- Denotes your terminal type. Each terminal type is distinct, though - many are similar. + You must also enable the wide-character features in the header + file when compiling for the wide-character library to use the + extended (wide-character) functions. The symbol which enables + these features has changed since X/Open Curses, Issue 4: - TERM is commonly set by terminal emulators to help applications find a - workable terminal description. Some of those choose a popular approxi- - mation, e.g., "ansi", "vt100", "xterm" rather than an exact fit. Not - infrequently, your application will have problems with that approach, - e.g., incorrect function-key definitions. + o Originally, the wide-character feature required the symbol + _XOPEN_SOURCE_EXTENDED but that was only valid for XPG4 + (1996). - If you set TERM in your environment, it has no effect on the operation - of the terminal emulator. It only affects the way applications work - within the terminal. Likewise, as a general rule (xterm being a rare - exception), terminal emulators which allow you to specify TERM as a - parameter or configuration value do not change their behavior to match - that setting. + o Later, that was deemed conflicting with _XOPEN_SOURCE defined + to 500. + o As of mid-2018, none of the features in this implementation + require a _XOPEN_SOURCE feature greater than 600. However, + X/Open Curses, Issue 7 (2009) recommends defining it to 700. -
- If the ncurses library has been configured with termcap support, - ncurses will check for a terminal's description in termcap form if it - is not available in the terminfo database. + o Alternatively, you can enable the feature by defining + NCURSES_WIDECHAR with the caveat that some other header file + than curses.h may require a specific value for _XOPEN_SOURCE + (or a system-specific symbol). - The TERMCAP environment variable contains either a terminal description - (with newlines stripped out), or a file name telling where the informa- - tion denoted by the TERM environment variable exists. In either case, - setting it directs ncurses to ignore the usual place for this informa- - tion, e.g., /etc/termcap. + The curses.h header file installed for the wide-character library + is designed to be compatible with the non-wide library's header. + Only the size of the WINDOW structure differs; few applications + require more than pointers to WINDOWs. + If the headers are installed allowing overwrite, the wide- + character library's headers should be installed last, to allow + applications to be built using either library from the same set of + headers. -
- ncurses can be configured to read from multiple terminal databases. - The TERMINFO variable overrides the location for the default terminal - database. Terminal descriptions (in terminal format) are stored in - terminal databases: + --with-pthread + The configure script renames the library. All of the library + names have a "t" appended to them (before any "w" added by + --enable-widec). - o Normally these are stored in a directory tree, using subdirectories - named by the first letter of the terminal names therein. + The global variables such as LINES are replaced by macros to allow + read-only access. At the same time, setter-functions are provided + to set these values. Some applications (very few) may require + changes to work with this convention. - This is the scheme used in System V, which legacy Unix systems use, - and the TERMINFO variable is used by curses applications on those - systems to override the default location of the terminal database. + --with-shared + --with-normal + --with-debug + --with-profile + The shared and normal (static) library names differ by their + suffixes, e.g., libncurses.so and libncurses.a. The debug and + profiling libraries add a "_g" and a "_p" to the root names + respectively, e.g., libncurses_g.a and libncurses_p.a. - o If ncurses is built to use hashed databases, then each entry in - this list may be the path of a hashed database file, e.g., + --with-termlib + Low-level functions which do not depend upon whether the library + supports wide-characters, are provided in the tinfo library. - /usr/share/terminfo.db + By doing this, it is possible to share the tinfo library between + wide/normal configurations as well as reduce the size of the + library when only low-level functions are needed. - rather than + Those functions are described in these pages: - /usr/share/terminfo/ + o curs_extend(3x) - miscellaneous curses extensions - The hashed database uses less disk-space and is a little faster - than the directory tree. However, some applications assume the - existence of the directory tree, reading it directly rather than - using the terminfo library calls. + o curs_inopts(3x) - curses input options - o If ncurses is built with a support for reading termcap files - directly, then an entry in this list may be the path of a termcap - file. + o curs_kernel(3x) - low-level curses routines - o If the TERMINFO variable begins with "hex:" or "b64:", ncurses uses - the remainder of that variable as a compiled terminal description. - You might produce the base64 format using infocmp(1m): + o curs_termattrs(3x) - curses environment query routines - TERMINFO="$(infocmp -0 -Q2 -q)" - export TERMINFO + o curs_termcap(3x) - curses emulation of termcap - The compiled description is used if it corresponds to the terminal - identified by the TERM variable. + o curs_terminfo(3x) - curses interface to terminfo database - Setting TERMINFO is the simplest, but not the only way to set location - of the default terminal database. The complete list of database loca- - tions in order follows: + o curs_util(3x) - miscellaneous curses utility routines - o the last terminal database to which ncurses wrote, if any, is - searched first + --with-trace + The trace function normally resides in the debug library, but it + is sometimes useful to configure this in the shared library. + Configure scripts should check for the function's existence rather + than assuming it is always in the debug library. - o the location specified by the TERMINFO environment variable - o $HOME/.terminfo +
+ /usr/share/tabset + tab stop initialization database - o locations listed in the TERMINFO_DIRS environment variable + /usr/share/terminfo + compiled terminal capability database - o one or more locations whose names are configured and compiled - into the ncurses library, i.e., - o /usr/local/ncurses/share/terminfo:/usr/share/terminfo (corre- - sponding to the TERMINFO_DIRS variable) +
+ X/Open Curses permits most functions it specifies to be made available + as macros as well. ncurses does so - o /usr/share/terminfo (corresponding to the TERMINFO variable) + o for functions that return values via their parameters, + o to support obsolete features, -
- Specifies a list of locations to search for terminal descriptions. - Each location in the list is a terminal database as described in the - section on the TERMINFO variable. The list is separated by colons - (i.e., ":") on Unix, semicolons on OS/2 EMX. + o to reuse functions (for example, those that move the cursor before + another operation), and - There is no corresponding feature in System V terminfo; it is an exten- - sion developed for ncurses. + o in a few special cases. + If the standard output file descriptor of an ncurses program is + redirected to something that is not a terminal device, the library + writes screen updates to the standard error file descriptor. This was + an undocumented feature of SVr3 curses. -
- If TERMCAP does not hold a file name then ncurses checks the TERMPATH - environment variable. This is a list of filenames separated by spaces - or colons (i.e., ":") on Unix, semicolons on OS/2 EMX. + See subsection "Header Files" below regarding symbols exposed by + inclusion of curses.h. - If the TERMPATH environment variable is not set, ncurses looks in the - files - /etc/termcap, /usr/share/misc/termcap and $HOME/.termcap, +
+ ncurses enables an application to capture mouse events on certain + terminals, including xterm(1); see curs_mouse(3x). - in that order. + ncurses provides a means of responding to window resizing events, as + when running in a GUI terminal emulator application such as xterm; see + resizeterm(3x) and wresize(3x). - The library may be configured to disregard the following variables when - the current user is the superuser (root), or if the application uses - setuid or setgid permissions: + ncurses allows an application to query the terminal for the presence of + a wide variety of special keys; see has_key(3x). - $TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME. + ncurses extends the fixed set of function key capabilities specified by + X/Open Curses by allowing the application programmer to define + additional key events at runtime; see define_key(3x), key_defined(3x), + keybound(3x), and keyok(3x). + ncurses can exploit the capabilities of terminals implementing + ISO 6429/ECMA-48 SGR 39 and SGR 49 sequences, which allow an + application to reset the terminal to its original foreground and + background colors. From a user's perspective, the application is able + to draw colored text on a background whose color is set independently, + providing better control over color contrasts. See default_colors(3x). -
- Several different configurations are possible, depending on the config- - ure script options used when building ncurses. There are a few main - options whose effects are visible to the applications developer using - ncurses: + An ncurses application can eschew knowledge of WINDOW structure + internals, instead using accessor functions such as is_scrollok(3x). - --disable-overwrite - The standard include for ncurses is as noted in SYNOPSIS: + ncurses enables an application to direct its output to a printer + attached to the terminal device; see curs_print(3x). - #include <curses.h> + ncurses offers slk_attr(3x) as a counterpart of attr_get(3x) for soft- + label key lines, and extended_slk_color(3x) as a form of slk_color(3x) + that can gather color information from them when many colors are + supported. - This option is used to avoid filename conflicts when ncurses is - not the main implementation of curses of the computer. If ncurses - is installed disabling overwrite, it puts its headers in a subdi- - rectory, e.g., + ncurses permits modification of unctrl(3x)'s behavior; see + use_legacy_coding(3x). - #include <ncurses/curses.h> + Rudimentary support for multi-threaded applications may be available; + see curs_threads(3x). - It also omits a symbolic link which would allow you to use - -lcurses to build executables. + Functions that ease the management of multiple screens can be exposed; + see curs_sp_funcs(3x). - --enable-widec - The configure script renames the library and (if the --dis- - able-overwrite option is used) puts the header files in a differ- - ent subdirectory. All of the library names have a "w" appended to - them, i.e., instead of + To aid applications to debug their memory usage, ncurses optionally + offers functions to more aggressively free memory it dynamically + allocates itself; see curs_memleaks(3x). - -lncurses + The library facilitates auditing and troubleshooting of its behavior; + see curs_trace(3x). - you link with + Compiling ncurses with the option -DUSE_GETCAP causes it to fall back + to reading /etc/termcap if the terminal setup code cannot find a term- + info entry corresponding to TERM. Use of this feature is not + recommended, as it essentially includes an entire termcap compiler in + the ncurses startup code, at a cost in memory usage and application + launch latency. - -lncursesw + PDCurses and NetBSD curses incorporate some ncurses extensions. + Individual man pages indicate where this is the case. - You must also define _XOPEN_SOURCE_EXTENDED when compiling for the - wide-character library to use the extended (wide-character) func- - tions. The curses.h file which is installed for the wide-charac- - ter library is designed to be compatible with the normal library's - header. Only the size of the WINDOW structure differs, and very - few applications require more than a pointer to WINDOWs. If the - headers are installed allowing overwrite, the wide-character - library's headers should be installed last, to allow applications - to be built using either library from the same set of headers. - - --with-pthread - The configure script renames the library. All of the library - names have a "t" appended to them (before any "w" added by - --enable-widec). - The global variables such as LINES are replaced by macros to allow - read-only access. At the same time, setter-functions are provided - to set these values. Some applications (very few) may require - changes to work with this convention. +
+ X/Open Curses defines two levels of conformance, "base" and "enhanced". + The latter includes several additional features, such as wide-character + and color support. ncurses intends base-level conformance with X/Open + Curses, and supports all features of its enhanced level except the + untic utility. - --with-shared + Differences between X/Open Curses and ncurses are documented in the + "PORTABILITY" sections of applicable man pages. - --with-normal - --with-debug +
+ In many cases, X/Open Curses is vague about error conditions, omitting + some of the SVr4 documentation. - --with-profile - The shared and normal (static) library names differ by their suf- - fixes, e.g., libncurses.so and libncurses.a. The debug and pro- - filing libraries add a "_g" and a "_p" to the root names respec- - tively, e.g., libncurses_g.a and libncurses_p.a. + Unlike other implementations, ncurses checks pointer parameters, such + as those to WINDOW structures, to ensure that they are not null. This + is done primarily to guard against programmer error. The standard + interface does not provide a way for the library to tell an application + which of several possible errors occurred. An application that relies + on ncurses to check its function parameters for validity limits its + portability and robustness. - --with-trace - The trace function normally resides in the debug library, but it - is sometimes useful to configure this in the shared library. Con- - figure scripts should check for the function's existence rather - than assuming it is always in the debug library. +
+ In historical curses implementations, delays embedded in the terminfo + capabilities carriage_return (cr), scroll_forward (ind), cursor_left + (cub1), form_feed (ff), and tab (ht) activated corresponding delay bits + in the Unix terminal driver. ncurses performs all padding by sending + NUL bytes to the device. This method is slightly more expensive, but + narrows the interface to the Unix kernel significantly and + correspondingly increases the package's portability. -
- /usr/share/tabset - directory containing initialization files for the terminal capa- - bility database /usr/share/terminfo terminal capability database +
+ The header file curses.h itself includes the header files stdio.h and + unctrl.h. -
- terminfo(5) and related pages whose names begin "curs_" for detailed - routine descriptions. - curs_variables(3x) - user_caps(5) for user-defined capabilities + X/Open Curses has more to say, + The inclusion of curses.h may make visible all symbols from the + headers stdio.h, term.h, termios.h, and wchar.h. -
- The ncurses library can be compiled with an option (-DUSE_GETCAP) that - falls back to the old-style /etc/termcap file if the terminal setup - code cannot find a terminfo entry corresponding to TERM. Use of this - feature is not recommended, as it essentially includes an entire term- - cap compiler in the ncurses startup code, at significant cost in core - and startup cycles. - - The ncurses library includes facilities for capturing mouse events on - certain terminals (including xterm). See the curs_mouse(3x) manual - page for details. - - The ncurses library includes facilities for responding to window resiz- - ing events, e.g., when running in an xterm. See the resizeterm(3x) and - wresize(3x) manual pages for details. In addition, the library may be - configured with a SIGWINCH handler. - - The ncurses library extends the fixed set of function key capabilities - of terminals by allowing the application designer to define additional - key sequences at runtime. See the define_key(3x) key_defined(3x), and - keyok(3x) manual pages for details. - - The ncurses library can exploit the capabilities of terminals which - implement the ISO-6429 SGR 39 and SGR 49 controls, which allow an - application to reset the terminal to its original foreground and back- - ground colors. From the users' perspective, the application is able to - draw colored text on a background whose color is set independently, - providing better control over color contrasts. See the default_col- - ors(3x) manual page for details. - - The ncurses library includes a function for directing application out- - put to a printer attached to the terminal device. See the - curs_print(3x) manual page for details. + but does not finish the story. A more complete account follows. + o The first curses, in 4BSD, provided a curses.h file. -
- The ncurses library is intended to be BASE-level conformant with XSI - Curses. The EXTENDED XSI Curses functionality (including color sup- - port) is supported. + BSD curses code included curses.h and unctrl.h from an internal + header file curses.ext, where "ext" abbreviated "externs". - A small number of local differences (that is, individual differences - between the XSI Curses and ncurses calls) are described in PORTABILITY - sections of the library man pages. + The implementations of printw and scanw used undocumented internal + functions of the standard I/O library (_doprnt and _doscan), but + nothing in curses.h itself relied upon stdio.h. - Unlike other implementations, this one checks parameters such as point- - ers to WINDOW structures to ensure they are not null. The main reason - for providing this behavior is to guard against programmer error. The - standard interface does not provide a way for the library to tell an - application which of several possible errors were detected. Relying on - this (or some other) extension will adversely affect the portability of - curses applications. + o SVr2 curses added newterm, which relies upon stdio.h because its + function prototype employs the FILE type. - This implementation also contains several extensions: + SVr4 curses added putwin and getwin, which also use stdio.h. - o The routine has_key is not part of XPG4, nor is it present in SVr4. - See the curs_getch(3x) manual page for details. + X/Open Curses specifies all three of these functions. - o The routine slk_attr is not part of XPG4, nor is it present in - SVr4. See the curs_slk(3x) manual page for details. + SVr4 curses and X/Open Curses do not require the developer to + include stdio.h before curses.h. Both document use of curses as + requiring only curses.h. - o The routines getmouse, mousemask, ungetmouse, mouseinterval, and - wenclose relating to mouse interfacing are not part of XPG4, nor - are they present in SVr4. See the curs_mouse(3x) manual page for - details. + As a result, standard curses.h always includes stdio.h. - o The routine mcprint was not present in any previous curses imple- - mentation. See the curs_print(3x) manual page for details. + o X/Open Curses and SVr4 curses are inconsistent with respect to + unctrl.h. - o The routine wresize is not part of XPG4, nor is it present in SVr4. - See the wresize(3x) manual page for details. + As noted in curs_util(3x), ncurses includes unctrl.h from curses.h + (as SVr4 does). - o The WINDOW structure's internal details can be hidden from applica- - tion programs. See curs_opaque(3x) for the discussion of is_scrol- - lok, etc. + o X/Open Curses's comments about term.h and termios.h may refer to + HP-UX and AIX. - o This implementation can be configured to provide rudimentary sup- - port for multi-threaded applications. See curs_threads(3x) for - details. + HP-UX curses includes term.h from curses.h to declare setupterm in + curses.h, but ncurses and Solaris curses do not. - o This implementation can also be configured to provide a set of - functions which improve the ability to manage multiple screens. - See curs_sp_funcs(3x) for details. + AIX curses includes term.h and termios.h. Again, ncurses and + Solaris curses do not. - In historic curses versions, delays embedded in the capabilities cr, - ind, cub1, ff and tab activated corresponding delay bits in the UNIX - tty driver. In this implementation, all padding is done by sending NUL - bytes. This method is slightly more expensive, but narrows the inter- - face to the UNIX kernel significantly and increases the package's - portability correspondingly. + o X/Open Curses says that curses.h may include term.h, but does not + require it to do so. + Some programs use functions declared in both curses.h and term.h, + and must include both header files in the same module. Very old + versions of AIX curses required inclusion of curses.h before + term.h. -
- The header file <curses.h> automatically includes the header files - <stdio.h> and <unctrl.h>. + The header files supplied by ncurses include the standard library + headers required for its declarations, so ncurses's own header + files can be included in any order. But for portability, you + should include curses.h before term.h. + + o X/Open Curses says "may make visible" because including a header + file does not necessarily make visible all of the symbols in it + (consider #ifdef and similar). + + For instance, ncurses's curses.h may include wchar.h if the proper + symbol is defined, and if ncurses is configured for wide-character + support. If wchar.h is included, its symbols may be made visible + depending on the value of the _XOPEN_SOURCE feature test macro. + + o X/Open Curses mandates an application's inclusion of one standard C + library header in a special case: stdarg.h before curses.h to + prototype the functions vw_printw and vw_scanw (as well as the + obsolete vwprintw and vwscanw). Each of these takes a variadic + argument list, a va_list parameter, like that of printf(3). - If standard output from a ncurses program is re-directed to something - which is not a tty, screen updates will be directed to standard error. - This was an undocumented feature of AT&T System V Release 3 curses. + SVr3 curses introduced the two obsolete functions, and X/Open + Curses the others. In between, SVr4 curses provided for the + possibility that an application might include either varargs.h or + stdarg.h. These represented contrasting approaches to handling + variadic argument lists. The older interface, varargs.h, used a + pointer to char for variadic functions' va_list parameter. Later, + the list acquired its own standard data type, va_list, defined in + stdarg.h, empowering the compiler to check the types of a function + call's actual parameters against the formal ones declared in its + prototype. + + No conforming implementations of X/Open Curses require an + application to include stdarg.h before curses.h because they either + have allowed for a special type, or, like ncurses, they include + stdarg.h themselves to provide a portable interface.
- Zeyd M. Ben-Halim, Eric S. Raymond, Thomas E. Dickey. Based on pcurses + Zeyd M. Ben-Halim, Eric S. Raymond, Thomas E. Dickey. Based on pcurses by Pavel Curtis. +
+ curs_variables(3x), terminfo(5), user_caps(5) + + - ncurses(3x) +ncurses 6.5 2024-05-25 ncurses(3x)