ncurses 6.3 - patch 20220729

[ncurses.git] / man / curs_getstr.3x

diff --git a/man/curs_getstr.3x b/man/curs_getstr.3x
index d9bed5958976a9ba009629519844dae38261614d..80a1c1ab80d20a6c3a6030d98b4986bd415d0959 100644 (file)
--- a/man/curs_getstr.3x
+++ b/man/curs_getstr.3x
@@ -1,5 +1,5 @@
 .\"***************************************************************************
 .\"***************************************************************************

-.\" Copyright 2018-2019,2020 Thomas E. Dickey                                *
+.\" Copyright 2018-2021,2022 Thomas E. Dickey                                *

 .\" Copyright 1998-2010,2017 Free Software Foundation, Inc.                  *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" Copyright 1998-2010,2017 Free Software Foundation, Inc.                  *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *


@@ -27,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: curs_getstr.3x,v 1.29 2020/02/02 23:34:34 tom Exp $
+.\" $Id: curs_getstr.3x,v 1.36 2022/02/12 20:07:29 tom Exp $

 .TH curs_getstr 3X ""
 .ie \n(.g .ds `` \(lq
 .el       .ds `` ``
 .TH curs_getstr 3X ""
 .ie \n(.g .ds `` \(lq
 .el       .ds `` ``


@@ -40,67 +40,77 @@
 .na
 .hy 0
 .SH NAME
 .na
 .hy 0
 .SH NAME

-\fBgetstr\fR,
-\fBgetnstr\fR,
-\fBwgetstr\fR,
-\fBwgetnstr\fR,
-\fBmvgetstr\fR,
-\fBmvgetnstr\fR,
-\fBmvwgetstr\fR,
-\fBmvwgetnstr\fR \- accept character strings from \fBcurses\fR terminal keyboard
+\fBgetstr\fP,
+\fBgetnstr\fP,
+\fBwgetstr\fP,
+\fBwgetnstr\fP,
+\fBmvgetstr\fP,
+\fBmvgetnstr\fP,
+\fBmvwgetstr\fP,
+\fBmvwgetnstr\fP \- accept character strings from \fBcurses\fP terminal keyboard

 .ad
 .hy
 .SH SYNOPSIS
 .ad
 .hy
 .SH SYNOPSIS

-\fB#include <curses.h>\fR
+\fB#include <curses.h>\fP

 .sp
 .sp

-\fBint getstr(char *str);\fR
+\fBint getstr(char *\fIstr\fB);\fR

 .br
 .br

-\fBint getnstr(char *str, int n);\fR
+\fBint getnstr(char *\fIstr\fB, int \fIn\fB);\fR

 .br
 .br

-\fBint wgetstr(WINDOW *win, char *str);\fR
+\fBint wgetstr(WINDOW *\fIwin\fB, char *\fIstr\fB);\fR

 .br
 .br

-\fBint wgetnstr(WINDOW *win, char *str, int n);\fR
-.br
-\fBint mvgetstr(int y, int x, char *str);\fR
+\fBint wgetnstr(WINDOW *\fIwin\fB, char *\fIstr\fB, int \fIn\fB);\fR
+.sp
+\fBint mvgetstr(int \fIy\fB, int \fIx\fB, char *\fIstr\fB);\fR

 .br
 .br

-\fBint mvwgetstr(WINDOW *win, int y, int x, char *str);\fR
+\fBint mvwgetstr(WINDOW *\fIwin\fB, int \fIy\fB, int \fIx\fB, char *\fIstr\fB);\fR

 .br
 .br

-\fBint mvgetnstr(int y, int x, char *str, int n);\fR
+\fBint mvgetnstr(int \fIy\fB, int \fIx\fB, char *\fIstr\fB, int \fIn\fB);\fR

 .br
 .br

-\fBint mvwgetnstr(WINDOW *, int y, int x, char *str, int n);\fR
+\fBint mvwgetnstr(WINDOW *\fIwin\fB, int \fIy\fB, int \fIx\fB, char *\fIstr\fB, int \fIn\fB);\fR

 .br
 .SH DESCRIPTION
 .br
 .SH DESCRIPTION

-The function \fBgetstr\fR is equivalent to a series of calls to \fBgetch\fR,
+The function \fBgetstr\fP is equivalent to a series of calls to \fBgetch\fP,

 until a newline or carriage return is received (the terminating character is
 not included in the returned string).
 .\" X/Open says also until EOf
 .\" X/Open says then an EOS is added to the result
 .\" X/Open doesn't mention n<0
 The resulting value is placed in the
 until a newline or carriage return is received (the terminating character is
 not included in the returned string).
 .\" X/Open says also until EOf
 .\" X/Open says then an EOS is added to the result
 .\" X/Open doesn't mention n<0
 The resulting value is placed in the

-area pointed to by the character pointer \fIstr\fR,
+area pointed to by the character pointer \fIstr\fP,

 followed by a NUL.
 .PP
 followed by a NUL.
 .PP

-\fBwgetnstr\fR reads at most \fIn\fR characters, thus preventing a possible
+The \fBgetnstr\fP function reads
+from the \fIstdscr\fP default window.
+The other functions, such as \fBwgetnstr\fP,
+read from the window given as a parameter.
+.PP
+\fBgetnstr\fP reads at most \fIn\fP characters, thus preventing a possible

 overflow of the input buffer.
 Any attempt to enter more characters (other
 than the terminating newline or carriage return) causes a beep.
 Function
 keys also cause a beep and are ignored.
 overflow of the input buffer.
 Any attempt to enter more characters (other
 than the terminating newline or carriage return) causes a beep.
 Function
 keys also cause a beep and are ignored.

-The \fBgetnstr\fR function reads
-from the \fIstdscr\fR default window.

 .PP
 .PP

-The user's erase and kill characters are interpreted.
-If keypad
-mode is on for the window, \fBKEY_LEFT\fR and \fBKEY_BACKSPACE\fR
-are both considered equivalent to the user's kill character.
+The user's \fIerase\fP and \fIkill\fP characters are interpreted:
+.bP
+The \fIerase\fP character (e.g., \fB^H\fP) erases the character
+at the end of the buffer, moving the cursor to the left.
+.IP
+If \fIkeypad\fP mode is on for the window,
+\fBKEY_LEFT\fP and \fBKEY_BACKSPACE\fP
+are both considered equivalent to the user's erase character.
+.bP
+The \fIkill\fP character (e.g., \fB^U\fP) erases the entire buffer,
+leaving the cursor at the beginning of the buffer.

 .PP
 .PP

-Characters input are echoed only if \fBecho\fR is currently on.
+Characters input are echoed only if \fBecho\fP is currently on.

 In that case,
 backspace is echoed as deletion of the previous character (typically a left
 motion).
 .SH RETURN VALUE
 In that case,
 backspace is echoed as deletion of the previous character (typically a left
 motion).
 .SH RETURN VALUE

-All routines return the integer \fBERR\fR upon failure and an \fBOK\fR (SVr4
-specifies only \*(``an integer value other than \fBERR\fR\*('') upon successful
+All routines return the integer \fBERR\fP upon failure and an \fBOK\fP (SVr4
+specifies only \*(``an integer value other than \fBERR\fP\*('') upon successful

 completion.
 .PP
 X/Open defines no error conditions.
 completion.
 .PP
 X/Open defines no error conditions.


@@ -118,27 +128,27 @@ Functions with a \*(``mv\*('' prefix first perform a cursor movement using
 \fBwmove\fP, and return an error if the position is outside the window,
 or if the window pointer is null.
 .SH NOTES
 \fBwmove\fP, and return an error if the position is outside the window,
 or if the window pointer is null.
 .SH NOTES

-Note that \fBgetstr\fR, \fBmvgetstr\fR, and \fBmvwgetstr\fR may be macros.
+Note that \fBgetstr\fP, \fBmvgetstr\fP, and \fBmvwgetstr\fP may be macros.

 .SH PORTABILITY
 These functions are described in the XSI Curses standard, Issue 4.
 They read single-byte characters only.
 The standard does not define any error conditions.
 This implementation returns \fBERR\fP if the window pointer is null,
 .SH PORTABILITY
 These functions are described in the XSI Curses standard, Issue 4.
 They read single-byte characters only.
 The standard does not define any error conditions.
 This implementation returns \fBERR\fP if the window pointer is null,

-or if the lower-level \fBwgetch\fR(3X) call returns an \fBERR\fP.
+or if the lower-level \fBwgetch\fP(3X) call returns an \fBERR\fP.

 .PP
 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,
 .PP
 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,

-\fIetc\fR.) are \*(``interpreted\*('',
+\fIetc\fP.) 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).
 .PP
 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).
 .PP

-The functions \fBgetnstr\fR, \fBmvgetnstr\fR, and \fBmvwgetnstr\fR were
+The functions \fBgetnstr\fP, \fBmvgetnstr\fP, and \fBmvwgetnstr\fP were

 present but not documented in SVr4.
 .PP
 X/Open Curses, Issue 5 (2007) stated that these functions
 present but not documented in SVr4.
 .PP
 X/Open Curses, Issue 5 (2007) stated that these functions


@@ -187,7 +197,50 @@ which the \fBsysconf\fP function may provide.
 If neither \fBLINE_MAX\fP or \fBsysconf\fP is available,
 ncurses uses the POSIX value for \fBLINE_MAX\fP (a 2048 byte limit).
 In either case, it reserves a byte for the terminating NUL.
 If neither \fBLINE_MAX\fP or \fBsysconf\fP is available,
 ncurses uses the POSIX value for \fBLINE_MAX\fP (a 2048 byte limit).
 In either case, it reserves a byte for the terminating NUL.

+.PP
+Although \fBgetnstr\fP is equivalent to a series of calls to \fBgetch\fP,
+it also makes changes to the curses modes to allow simple editing of
+the input buffer:
+.bP
+\fBgetnstr\fP saves the current value of the \fBnl\fP, \fBecho\fP,
+\fBraw\fP and \fBcbreak\fP modes, and sets
+\fBnl\fP,
+\fBnoecho\fP,
+\fBnoraw\fP, and
+\fBcbreak\fP.
+.IP
+\fBgetnstr\fP handles the echoing of characters,
+rather than relying on the caller to set an appropriate mode.
+.bP
+It also obtains the \fIerase\fP and \fIkill\fP characters
+from \fBerasechar\fP and \fBkillchar\fP, respectively.
+.bP
+On return, \fBgetnstr\fP restores the modes to their previous values.
+.PP
+Other implementations differ in their treatment of special characters:
+.bP
+While they may set the \fIecho\fP mode,
+other implementations do not modify the \fIraw\fP mode,
+They may take the \fIcbreak\fP
+mode set by the caller into account when deciding whether to handle
+echoing within \fBgetnstr\fP or as a side-effect of the \fBgetch\fP calls.
+.bP
+The original ncurses (as \fIpcurses\fP in 1986) set \fBnoraw\fP and \fBcbreak\fP
+when accepting input for \fBgetnstr\fP.
+That may have been done to make function- and cursor-keys work;
+it is not necessary with ncurses.
+.IP
+Since 1995, ncurses has provided signal handlers for INTR and QUIT
+(e.g., \fB^C\fP or \fB^\\\fP).
+With the \fBnoraw\fP and \fBcbreak\fP settings,
+those may catch a signal and stop the program,
+where other implementations allow one to enter those characters in the buffer.
+.bP
+Starting in 2021 (ncurses 6.3), \fBgetnstr\fP sets \fBraw\fP,
+rather than \fBnoraw\fP and \fBcbreak\fP for better compatibility with
+SVr4-curses, e.g., allowing one to enter a \fB^C\fP into the buffer.

 .SH SEE ALSO
 .SH SEE ALSO

-\fBcurses\fR(3X),
-\fBcurs_getch\fR(3X),
-\fBcurs_variables\fR(3X).
+\fBcurses\fP(3X),
+\fBcurs_getch\fP(3X),
+\fBcurs_termattrs\fP(3X),
+\fBcurs_variables\fP(3X).