diff options
| author | Baptiste Daroussin <bapt@FreeBSD.org> | 2026-01-14 13:37:49 +0100 |
|---|---|---|
| committer | Baptiste Daroussin <bapt@FreeBSD.org> | 2026-01-14 13:37:49 +0100 |
| commit | c5a1e08b52b2f6c05e0116d46277904b711b6bdb (patch) | |
| tree | a6ad7350d1b1100356ca59616d22c51dd29743eb /doc/html/man/curs_getstr.3x.html | |
| parent | 24fa7a5107c5b75d1c197accf0305be64bc72882 (diff) | |
Vendor import ncurses 6.6vendor/ncurses/6.6vendor/ncurses
Diffstat (limited to 'doc/html/man/curs_getstr.3x.html')
| -rw-r--r-- | doc/html/man/curs_getstr.3x.html | 292 |
1 files changed, 161 insertions, 131 deletions
diff --git a/doc/html/man/curs_getstr.3x.html b/doc/html/man/curs_getstr.3x.html index 0142df971c21..97565fcac72a 100644 --- a/doc/html/man/curs_getstr.3x.html +++ b/doc/html/man/curs_getstr.3x.html @@ -1,6 +1,6 @@ <!-- **************************************************************************** - * Copyright 2018-2023,2024 Thomas E. Dickey * + * Copyright 2018-2024,2025 Thomas E. Dickey * * Copyright 1998-2010,2017 Free Software Foundation, Inc. * * * * Permission is hereby granted, free of charge, to any person obtaining a * @@ -27,222 +27,250 @@ * sale, use or other dealings in this Software without prior written * * authorization. * **************************************************************************** - * @Id: curs_getstr.3x,v 1.58 2024/04/20 19:18:18 tom Exp @ + * @Id: curs_getstr.3x,v 1.94 2025/10/21 00:09:04 tom Exp @ --> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <HTML> <HEAD> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts"> -<TITLE>curs_getstr 3x 2024-04-20 ncurses 6.5 Library calls</TITLE> +<TITLE>curs_getstr 3x 2025-10-20 ncurses 6.6 Library calls</TITLE> <link rel="author" href="mailto:bug-ncurses@gnu.org"> </HEAD> <BODY> -<H1 class="no-header">curs_getstr 3x 2024-04-20 ncurses 6.5 Library calls</H1> +<H1 class="no-header">curs_getstr 3x 2025-10-20 ncurses 6.6 Library calls</H1> <PRE> <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG> - - </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE> <STRONG>getstr</STRONG>, <STRONG>getnstr</STRONG>, <STRONG>wgetstr</STRONG>, <STRONG>wgetnstr</STRONG>, <STRONG>mvgetstr</STRONG>, <STRONG>mvgetnstr</STRONG>, <STRONG>mvwgetstr</STRONG>, - <STRONG>mvwgetnstr</STRONG> - accept character strings from <EM>curses</EM> terminal keyboard + <STRONG>mvwgetnstr</STRONG> - read a character string from <EM>curses</EM> terminal keyboard </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE> <STRONG>#include</STRONG> <STRONG><curses.h></STRONG> - <STRONG>int</STRONG> <STRONG>getstr(char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>getnstr(char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>wgetstr(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>wgetnstr(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>getstr(char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>wgetstr(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>mvgetstr(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>mvwgetstr(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>mvgetstr(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>mvwgetstr(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>mvgetnstr(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> - <STRONG>int</STRONG> <STRONG>mvwgetnstr(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>getnstr(char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>wgetnstr(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>mvgetnstr(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> + <STRONG>int</STRONG> <STRONG>mvwgetnstr(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>str</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG> </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE> - The function <STRONG>wgetnstr</STRONG> is equivalent to a series of calls to <STRONG><A HREF="curs_getch.3x.html">wgetch(3x)</A></STRONG>, - until a newline or carriage return terminates the series: + <STRONG>wgetstr</STRONG> populates a user-supplied string buffer <EM>str</EM> by repeatedly + calling <STRONG><A HREF="curs_getch.3x.html">wgetch(3x)</A></STRONG> with the <EM>win</EM> argument until a line feed or carriage + return character is input. The function - <STRONG>o</STRONG> The terminating character is not included in the returned string. + <STRONG>o</STRONG> does not copy the terminating character to <EM>str</EM>; - <STRONG>o</STRONG> In all instances, the end of the string is terminated by a NUL. + <STRONG>o</STRONG> always terminates <EM>str</EM> with a null character; - <STRONG>o</STRONG> The function stores the result in the area pointed to by the <EM>str</EM> - parameter. + <STRONG>o</STRONG> interprets the screen's erase and kill characters (see + <STRONG><A HREF="curs_termattrs.3x.html">erasechar(3x)</A></STRONG> and <STRONG><A HREF="curs_termattrs.3x.html">killchar(3x)</A></STRONG>); - <STRONG>o</STRONG> The function reads at most <EM>n</EM> characters, thus preventing a possible - overflow of the input buffer. + <STRONG>o</STRONG> recognizes function keys only if the screen's keypad option is + enabled (see <STRONG><A HREF="curs_inopts.3x.html">keypad(3x)</A></STRONG>); - Any attempt to enter more characters (other than the terminating - newline or carriage return) causes a beep. + <STRONG>o</STRONG> treats the function keys <STRONG>KEY_LEFT</STRONG> and <STRONG>KEY_BACKSPACE</STRONG> the same as the + erase character; and - Function keys also cause a beep and are ignored. + <STRONG>o</STRONG> discards function key inputs other than those treated as the erase + or kill characters, calling <STRONG><A HREF="curs_beep.3x.html">beep(3x)</A></STRONG>. - The user's <EM>erase</EM> and <EM>kill</EM> characters are interpreted: + If any characters have been written to the input buffer, the erase + character replaces the character at the current position in the buffer + with a null character, then decrements the position by one; the kill + character does the same repeatedly, backtracking to the beginning of + the buffer. - <STRONG>o</STRONG> The <EM>erase</EM> character (e.g., <STRONG>^H</STRONG>) erases the character at the end of - the buffer, moving the cursor to the left. + If the screen's echo option is enabled (see <STRONG><A HREF="curs_inopts.3x.html">echo(3x)</A></STRONG>), <STRONG>wgetstr</STRONG> updates + <EM>win</EM> with <STRONG><A HREF="curs_addch.3x.html">waddch(3x)</A></STRONG>. Further, - If <EM>keypad</EM> mode is on for the window, <STRONG>KEY_LEFT</STRONG> and <STRONG>KEY_BACKSPACE</STRONG> are - both considered equivalent to the user's <EM>erase</EM> character. + <STRONG>o</STRONG> the erase character and its function key synonyms move the cursor + to the left (if not already where it was located when <STRONG>wgetstr</STRONG> was + called) and - <STRONG>o</STRONG> The <EM>kill</EM> character (e.g., <STRONG>^U</STRONG>) erases the entire buffer, leaving the - cursor at the beginning of the buffer. + <STRONG>o</STRONG> the kill character returns the cursor to where it was located when + <STRONG>wgetstr</STRONG> was called. - Characters input are echoed only if <STRONG>echo</STRONG> is currently on. In that - case, backspace is echoed as deletion of the previous character - (typically a left motion). + <STRONG>wgetnstr</STRONG> is similar, but reads at most <EM>n</EM> characters, aiding the + application to avoid overrunning the buffer to which <EM>str</EM> points. + <EM>curses</EM> ignores an attempt to input more than <EM>n</EM> characters (other than + the terminating line feed or carriage return), calling <STRONG><A HREF="curs_beep.3x.html">beep(3x)</A></STRONG>. If <EM>n</EM> + is negative, <STRONG>wgetn_wstr</STRONG> reads up to <EM>LINE</EM><STRONG>_</STRONG><EM>MAX</EM> characters (see + <STRONG>sysconf(3)</STRONG>). - The <STRONG>getnstr</STRONG>, <STRONG>mvgetnstr</STRONG>, <STRONG>mvwgetnstr</STRONG>, and <STRONG>wgetnstr</STRONG> functions are - identical to the <STRONG>getstr</STRONG>, <STRONG>mvgetstr</STRONG>, <STRONG>mvwgetstr</STRONG>, and <STRONG>wgetstr</STRONG> functions, - respectively, except that the <STRONG>*n*</STRONG> versions read at most <EM>n</EM> characters, - letting the application prevent overflow of the input buffer. + <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG> describes the variants of these functions. </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE> - All of these functions return the integer <STRONG>OK</STRONG> upon successful - completion. (SVr4 specifies only "an integer value other than <STRONG>ERR</STRONG>") If - unsuccessful, they return <STRONG>ERR</STRONG>. + These functions return <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure. - X/Open defines no error conditions. + In <EM>ncurses</EM>, these functions fail if - In this implementation, these functions return an error + <STRONG>o</STRONG> the <EM>curses</EM> screen has not been initialized, - <STRONG>o</STRONG> if the window pointer is null, + <STRONG>o</STRONG> (for functions taking a <EM>WINDOW</EM> pointer argument) <EM>win</EM> is a null + pointer, - <STRONG>o</STRONG> if its timeout expires without having any data, or + <STRONG>o</STRONG> <EM>str</EM> is a null pointer, or - <STRONG>o</STRONG> if the associated call to <STRONG>wgetch</STRONG> failed. + <STRONG>o</STRONG> an internal <STRONG><A HREF="curs_getch.3x.html">wgetch(3x)</A></STRONG> call fails. - This implementation provides an extension as well. If a <STRONG>SIGWINCH</STRONG> - interrupts the function, it will return <STRONG>KEY_RESIZE</STRONG> rather than <STRONG>OK</STRONG> or - <STRONG>ERR</STRONG>. + Further, in <EM>ncurses</EM>, these functions return <STRONG>KEY_RESIZE</STRONG> if a <EM>SIGWINCH</EM> + event interrupts the function. Functions prefixed with "mv" first perform cursor movement and fail if the position (<EM>y</EM>, <EM>x</EM>) is outside the window boundaries. </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE> - Any of these functions other than <STRONG>wgetnstr</STRONG> may be macros. + All of these functions except <STRONG>wgetnstr</STRONG> may be implemented as macros. - Using <STRONG>getstr</STRONG>, <STRONG>mvgetstr</STRONG>, <STRONG>mvwgetstr</STRONG>, or <STRONG>wgetstr</STRONG> to read a line that - overflows the array pointed to by <STRONG>str</STRONG> causes undefined results. The - use of <STRONG>getnstr</STRONG>, <STRONG>mvgetnstr</STRONG>, <STRONG>mvwgetnstr</STRONG>, or <STRONG>wgetnstr</STRONG>, respectively, is - recommended. + Reading input that overruns the buffer pointed to by <EM>str</EM> causes + undefined results. Use the <STRONG>n</STRONG>-infixed functions, and allocate + sufficient storage for <EM>str</EM> -- at least <EM>n</EM>+1 times <STRONG>sizeof(char)</STRONG>. + While these functions conceptually implement a series of calls to + <STRONG>wgetch</STRONG>, they also temporarily change properties of the <EM>curses</EM> screen to + permit simple editing of the input buffer. Each function saves the + screen's state, calls <STRONG><A HREF="curs_inopts.3x.html">nl(3x)</A></STRONG>, and, if the screen was in canonical + ("cooked") mode, <STRONG><A HREF="curs_inopts.3x.html">cbreak(3x)</A></STRONG>. Before returning, it restores the saved + screen state. Other implementations differ in detail, affecting which + control characters they can accept in the buffer; see section + "PORTABILITY" below. -</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE> - These functions are described in The Single Unix Specification, Version - 2. No error conditions are defined. - This implementation returns <STRONG>ERR</STRONG> if the window pointer is null, or if - the lower-level <STRONG><A HREF="curs_getch.3x.html">wgetch(3x)</A></STRONG> call returns an <STRONG>ERR</STRONG>. +</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE> + <STRONG>getnstr</STRONG>, <STRONG>wgetnstr</STRONG>, <STRONG>mvgetnstr</STRONG>, and <STRONG>mvwgetnstr</STRONG>'s handing of negative <EM>n</EM> + values is an <EM>ncurses</EM> extension. - SVr3 and early SVr4 curses implementations did not reject function - keys; the SVr4.0 documentation claimed that "special keys" (such as - function keys, "home" key, "clear" key, <EM>etc</EM>.) are "interpreted", - without giving details. It lied. In fact, the "character" value - appended to the string by those implementations was predictable but not - useful (being, in fact, the low-order eight bits of the key's KEY_ - value). + The return value <STRONG>KEY_RESIZE</STRONG> is an <EM>ncurses</EM> extension. - The functions <STRONG>getnstr</STRONG>, <STRONG>mvgetnstr</STRONG>, and <STRONG>mvwgetnstr</STRONG> were present but not - documented in SVr4. - X/Open Curses, Issue 5 (2007) stated that these functions "read at most - <EM>n</EM> bytes" but did not state whether the terminating NUL is counted in - that limit. X/Open Curses, Issue 7 (2009) changed that to say they - "read at most <EM>n</EM>-1 bytes" to allow for the terminating NUL. As of 2018, - some implementations count it, some do not: +</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE> + Applications employing <EM>ncurses</EM> extensions should condition their use on + the visibility of the <STRONG>NCURSES_VERSION</STRONG> preprocessor macro. + + X/Open Curses Issue 4 describes these functions. It specifies no error + conditions for them, but indicates that <EM>wgetnstr</EM> and its variants read + "the entire multi-byte sequence associated with a character" and "fail" + if <EM>n</EM> and <EM>str</EM> together do not describe a buffer "large enough to contain + any complete characters". In <EM>ncurses</EM>, however, <EM>wgetch</EM> reads only + single-byte characters, so this scenario does not arise. + + SVr4 describes a successful return value only as "an integer value + other than <EM>ERR</EM>". - <STRONG>o</STRONG> <EM>ncurses</EM> 6.1 and PDCurses do not count the NUL in the given limit, - while + SVr3 and early SVr4 <EM>curses</EM> implementations did not reject function + keys; the SVr4 documentation asserted that, like the screen's erase and + kill characters, they were - <STRONG>o</STRONG> Solaris SVr4 and NetBSD curses count the NUL as part of the limit. + interpreted, as well as any special keys (such as function keys, + "home" key, "clear" key, <EM>etc.</EM>) - <STRONG>o</STRONG> Solaris xcurses provides both: its wide-character <STRONG>wget_nstr</STRONG> - reserves a NUL, but its <STRONG>wgetnstr</STRONG> does not count the NUL - consistently. + without further detail. It lied. The "character" value appended to + the string by those implementations was predictable but not useful -- + being, in fact, the low-order eight bits of the key code's <EM>KEY</EM><STRONG>_</STRONG> + constant value. (The same language, unchanged except for styling, + survived into X/Open Curses Issue 4, Version 2 but disappeared from + Issue 7.) - In SVr4 curses, a negative value of <EM>n</EM> tells <STRONG>wgetnstr</STRONG> to assume that the - caller's buffer is large enough to hold the result, i.e., to act like - <STRONG>wgetstr</STRONG>. X/Open Curses does not mention this (or anything related to - negative or zero values of <EM>n</EM>), however most implementations use the - feature, with different limits: + A draft of X/Open Curses Issue 5 (which never saw final release) stated + that these functions "read at most <EM>n</EM> bytes" but did not state whether + the terminating null character counted toward that limit. X/Open + Curses Issue 7 changed that to say they "read at most <EM>n</EM>-1 bytes" to + allow for the terminating null character. As of 2018, some + implementations count it, some do not. - <STRONG>o</STRONG> Solaris SVr4 curses and PDCurses limit the result to 255 bytes. - Other Unix systems than Solaris are likely to use the same limit. + <STRONG>o</STRONG> <EM>ncurses</EM> 6.1 and <EM>PDCurses</EM> do not count the null character toward the + limit, while Solaris and NetBSD <EM>curses</EM> do. - <STRONG>o</STRONG> Solaris xcurses limits the result to <STRONG>LINE_MAX</STRONG> bytes. + <STRONG>o</STRONG> Solaris <EM>xcurses</EM> offers both behaviors: its wide-character + <EM>wgetn</EM><STRONG>_</STRONG><EM>wstr</EM> reserves room for a wide null character, but its non- + wide <EM>wgetnstr</EM> does not consistently count a null character toward + the limit. - <STRONG>o</STRONG> NetBSD 7 assumes no particular limit for the result from <STRONG>wgetstr</STRONG>. - However, it limits the <STRONG>wgetnstr</STRONG> parameter <EM>n</EM> to ensure that it is - greater than zero. + X/Open Curses does not specify what happens if the length <EM>n</EM> is + negative. - A comment in NetBSD's source code states that this is specified in - SUSv2. + <STRONG>o</STRONG> <EM>ncurses</EM> 6.2 uses <EM>LINE</EM><STRONG>_</STRONG><EM>MAX</EM> or a larger (system-dependent) value + provided by <STRONG>sysconf(3)</STRONG>. If neither <EM>LINE</EM><STRONG>_</STRONG><EM>MAX</EM> nor <EM>sysconf</EM> is + available, <EM>ncurses</EM> uses the POSIX minimum value for <EM>LINE</EM><STRONG>_</STRONG><EM>MAX</EM> + (2048). In either case, it reserves a byte for the terminating + null character. - <STRONG>o</STRONG> <EM>ncurses</EM> (before 6.2) assumes no particular limit for the result - from <STRONG>wgetstr</STRONG>, and treats the <EM>n</EM> parameter of <STRONG>wgetnstr</STRONG> like SVr4 - curses. + <STRONG>o</STRONG> In SVr4 <EM>curses</EM>, a negative <EM>n</EM> tells <EM>wgetnstr</EM> to assume that the + caller's buffer is large enough to hold the result; that is, the + function then acts like <EM>wgetstr</EM>. X/Open Curses does not mention + this behavior (or anything related to nonpositive <EM>n</EM> values), + however most <EM>curses</EM> libraries implement it. Most implementations + nevertheless enforce an upper limit on the count of bytes they + write to the destination buffer <EM>str</EM>. - <STRONG>o</STRONG> <EM>ncurses</EM> 6.2 uses <STRONG>LINE_MAX</STRONG>, or a larger (system-dependent) value - which the <STRONG>sysconf</STRONG> function may provide. If neither <STRONG>LINE_MAX</STRONG> or - <STRONG>sysconf</STRONG> is available, <EM>ncurses</EM> uses the POSIX value for <STRONG>LINE_MAX</STRONG> (a - 2048 byte limit). In either case, it reserves a byte for the - terminating NUL. + <STRONG>o</STRONG> BSD <EM>curses</EM> lacked <EM>wgetnstr</EM>, and its <EM>wgetstr</EM> wrote to <EM>str</EM> + unboundedly, as did that in SVr2. - Although <STRONG>getnstr</STRONG> is equivalent to a series of calls to <STRONG>getch</STRONG>, it also - makes changes to the curses modes to allow simple editing of the input - buffer: + <STRONG>o</STRONG> <EM>PDCurses</EM>, and SVr3 and later, and Solaris <EM>curses</EM> limit both + functions to writing 256 bytes. Other System V-based platforms + likely use the same limit. - <STRONG>o</STRONG> <STRONG>getnstr</STRONG> saves the current value of the <STRONG>nl</STRONG>, <STRONG>echo</STRONG>, <STRONG>raw</STRONG> and <STRONG>cbreak</STRONG> - modes, and sets <STRONG>nl</STRONG>, <STRONG>noecho</STRONG>, <STRONG>noraw</STRONG>, and <STRONG>cbreak</STRONG>. + <STRONG>o</STRONG> Solaris <EM>xcurses</EM> limits the write to <EM>LINE</EM><STRONG>_</STRONG><EM>MAX</EM> bytes (see + <STRONG>sysconf(3)</STRONG>). - <STRONG>getnstr</STRONG> handles the echoing of characters, rather than relying on - the caller to set an appropriate mode. + <STRONG>o</STRONG> NetBSD 7 <EM>curses</EM> imposes no particular limit on the length of the + write, but does validate <EM>n</EM> to ensure that it is greater than zero. + A comment in NetBSD's source code asserts that SUSv2 specifies + this. - <STRONG>o</STRONG> It also obtains the <EM>erase</EM> and <EM>kill</EM> characters from <STRONG>erasechar</STRONG> and - <STRONG>killchar</STRONG>, respectively. + Implementations vary in their handling of input control characters. - <STRONG>o</STRONG> On return, <STRONG>getnstr</STRONG> restores the modes to their previous values. + <STRONG>o</STRONG> While they may enable the screen's echo option, some do not take it + out of raw mode, and may take cbreak mode into account when + deciding whether to handle echoing within <EM>wgetnstr</EM> or to rely on it + as a side effect of calling <EM>wgetch</EM>. - Other implementations differ in their treatment of special characters: + <STRONG>o</STRONG> Originally, <EM>ncurses</EM>, like its progenitor <EM>pcurses</EM>, had its <EM>wgetnstr</EM> + call <EM>noraw</EM> and <EM>cbreak</EM> before accepting input. That may have been + done to make function keys work; it is not necessary with modern + <EM>ncurses</EM>. - <STRONG>o</STRONG> While they may set the <EM>echo</EM> mode, other implementations do not - modify the <EM>raw</EM> mode, They may take the <EM>cbreak</EM> mode set by the - caller into account when deciding whether to handle echoing within - <STRONG>getnstr</STRONG> or as a side-effect of the <STRONG>getch</STRONG> calls. + Since 1995, <EM>ncurses</EM> has provided handlers for <EM>SIGINTR</EM> and <EM>SIGQUIT</EM> + events, which are typically generated at the keyboard with <STRONG>^C</STRONG> and + <STRONG>^\</STRONG> respectively. In cbreak mode, those handlers catch a signal and + stop the program, whereas other implementations write those + characters into the buffer. - <STRONG>o</STRONG> The original <EM>ncurses</EM> (as <EM>pcurses</EM> in 1986) set <STRONG>noraw</STRONG> and <STRONG>cbreak</STRONG> when - accepting input for <STRONG>getnstr</STRONG>. That may have been done to make - function- and cursor-keys work; it is not necessary with <EM>ncurses</EM>. + <STRONG>o</STRONG> Starting with <EM>ncurses</EM> 6.3 (2021), <EM>wgetnstr</EM> preserves raw mode if + the screen was already in that state, allowing one to enter the + characters the terminal interprets as interrupt and quit events + into the buffer, for better compatibility with SVr4 <EM>curses</EM>. - Since 1995, <EM>ncurses</EM> has provided signal handlers for INTR and QUIT - (e.g., <STRONG>^C</STRONG> or <STRONG>^\</STRONG>). With the <STRONG>noraw</STRONG> and <STRONG>cbreak</STRONG> settings, those may - catch a signal and stop the program, where other implementations - allow one to enter those characters in the buffer. - <STRONG>o</STRONG> Starting in 2021 (<EM>ncurses</EM> 6.3), <STRONG>getnstr</STRONG> sets <STRONG>raw</STRONG>, rather than <STRONG>noraw</STRONG> - and <STRONG>cbreak</STRONG> for better compatibility with SVr4-curses, e.g., - allowing one to enter a <STRONG>^C</STRONG> into the buffer. +</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE> + 4BSD (1980) introduced <EM>wgetstr</EM> along with its variants. + + SVr3.1 (1987) added <EM>wgetnstr</EM>, but none of its variants. + + X/Open Curses Issue 4 (1995) specified <EM>getnstr</EM>, <EM>mvgetnstr</EM>, and + <EM>mvwgetnstr</EM>. </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE> <STRONG><A HREF="curs_get_wstr.3x.html">curs_get_wstr(3x)</A></STRONG> describes comparable functions of the <EM>ncurses</EM> library in its wide-character configuration (<EM>ncursesw</EM>). - <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>, <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG> - - + <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>, <STRONG><A HREF="curs_getch.3x.html">curs_getch(3x)</A></STRONG>, <STRONG><A HREF="curs_inopts.3x.html">curs_inopts(3x)</A></STRONG>, + <STRONG><A HREF="curs_termattrs.3x.html">curs_termattrs(3x)</A></STRONG>, -ncurses 6.5 2024-04-20 <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG> +ncurses 6.6 2025-10-20 <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG> </PRE> <div class="nav"> <ul> @@ -251,7 +279,9 @@ ncurses 6.5 2024-04-20 <STRONG><A HREF=" <li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li> <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li> <li><a href="#h2-NOTES">NOTES</a></li> +<li><a href="#h2-EXTENSIONS">EXTENSIONS</a></li> <li><a href="#h2-PORTABILITY">PORTABILITY</a></li> +<li><a href="#h2-HISTORY">HISTORY</a></li> <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li> </ul> </div> |