'\" t
.\"***************************************************************************
-.\" Copyright (c) 1998-2015,2017 Free Software Foundation, Inc. *
+.\" Copyright 2018-2019,2020 Thomas E. Dickey *
+.\" Copyright 1998-2015,2017 Free Software Foundation, Inc. *
.\" *
.\" Permission is hereby granted, free of charge, to any person obtaining a *
.\" copy of this software and associated documentation files (the *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_util.3x,v 1.49 2017/05/30 21:09:21 tom Exp $
+.\" $Id: curs_util.3x,v 1.57 2020/02/02 23:34:34 tom Exp $
.TH curs_util 3X ""
.ie \n(.g .ds `` \(lq
.el .ds `` ``
.ie \n(.g .ds '' \(rq
.el .ds '' ''
.de bP
-.IP \(bu 4
+.ie n .IP \(bu 4
+.el .IP \(bu 2
..
.na
.hy 0
.SH SYNOPSIS
\fB#include <curses.h>\fR
.sp
-\fBchar *unctrl(chtype c);\fR
+\fBconst char *unctrl(chtype c);\fR
.br
\fBwchar_t *wunctrl(cchar_t *c);\fR
.br
-\fBchar *keyname(int c);\fR
+\fBconst char *keyname(int c);\fR
.br
-\fBchar *key_name(wchar_t w);\fR
+\fBconst char *key_name(wchar_t w);\fR
.br
\fBvoid filter(void);\fR
.br
.bP
Otherwise (if there is no corresponding name) the function returns null,
to denote an error.
-X/Open also lists an "UNKNOWN KEY" return value, which some implementations
-return rather than null.
+X/Open also lists an \*(``UNKNOWN KEY\*('' return value,
+which some implementations return rather than null.
.LP
The corresponding \fBkey_name\fR returns a character string corresponding
to the wide-character value \fIw\fR.
.PP
The \fBfilter\fR routine, if used, must be called before \fBinitscr\fR or
\fBnewterm\fR are called.
-The effect is that, during those calls, \fBLINES\fR
-is set to 1; the capabilities \fBclear\fR, \fBcup\fR, \fBcud\fR, \fBcud1\fR,
-\fBcuu1\fR, \fBcuu\fR, \fBvpa\fR are disabled; and the \fBhome\fR string is
-set to the value of \fBcr\fR.
+Calling \fBfilter\fP causes these changes in initialization:
+.bP
+\fBLINES\fR is set to 1;
+.bP
+the capabilities
+\fBclear\fR,
+\fBcud1\fR,
+\fBcud\fR,
+\fBcup\fR,
+\fBcuu1\fR,
+\fBcuu\fR,
+\fBvpa\fR
+are disabled;
+.bP
+the capability \fBed\fP is disabled if \fBbce\fP is set;
+.bP
+and the \fBhome\fR string is set to the value of \fBcr\fR.
.PP
The \fBnofilter\fP routine cancels the effect of a preceding \fBfilter\fP
call.
.IP
If \fBuse_env\fP was called with \fBFALSE\fP for parameter,
it stops here unless
-If \fBuse_tioctl\fP was also called with \fBTRUE\fP for parameter.
+\fBuse_tioctl\fP was also called with \fBTRUE\fP for parameter.
.bP
Then it asks for the screen size via operating system calls.
If successful,
should be called before \fBinitscr\fR or \fBnewterm\fR are called
(because those compute the screen size).
After \fBuse_tioctl\fR is called with \fBTRUE\fR as an argument,
-\fBncurses\fP modifies the last step in its computation of screen size as follows:
+\fBncurses\fP modifies the last step in its computation
+of screen size as follows:
.bP
checks if the \fBLINES\fR and \fBCOLUMNS\fR environment variables
are set to a number greater than zero.
\fBncurses\fP updates $LINES and $COLUMNS based on operating system calls.
T}
FALSE/TRUE/T{
-\fBncurses\fP ignores $LINES and $COLUMNS, uses operating system calls to obtain size.
+\fBncurses\fP ignores $LINES and $COLUMNS,
+uses operating system calls to obtain size.
T}
FALSE/FALSE/T{
\fBncurses\fP relies on the terminal database to determine size.
.bP
the data written is a copy of the \fBWINDOW\fP structure,
and its associated character cells.
-The format differs between the wide-character (ncursesw) and
-non-wide (ncurses) libraries.
+The format differs between the wide-character (\fBncursesw\fP) and
+non-wide (\fBncurses\fP) libraries.
You can transfer data between the two, however.
.bP
the retrieved window is always created as a top-level window (or pad),
string capabilities which are defined in the terminfo entry via the \fB\-x\fP
option of \fB@TIC@\fP.
This implementation automatically assigns at run-time keycodes to
-user-defined strings which begin with "k".
+user-defined strings which begin with \*(``k\*(''.
The keycodes start at KEY_MAX, but are not guaranteed to be
the same value for different runs because user-defined codes are
merged from all terminal descriptions which have been loaded.
Oddly, there are no such functions in the 4.3BSD curses sources.
.bP
Most implementations simply dump the binary \fBWINDOW\fP structure to the file.
-These include SVr4 curses, NetBSD and PDCurses, as well as older \fBncurses\fP versions.
-This implementation (as well as the X/Open variant of Solaris curses, dated 1995)
+These include SVr4 curses, NetBSD and PDCurses,
+as well as older \fBncurses\fP versions.
+This implementation
+(as well as the X/Open variant of Solaris curses, dated 1995)
uses textual dumps.
.IP
The implementations which use binary dumps use block-I/O
.PP
The strings returned by \fBunctrl\fR in this implementation are determined
at compile time,
-showing C1 controls from the upper-128 codes with a \*(``~\*('' prefix rather than \*(``^\*(''.
+showing C1 controls from the upper-128 codes
+with a \*(``~\*('' prefix rather than \*(``^\*(''.
Other implementations have different conventions.
For example, they may show both sets of control characters with \*(``^\*('',
and strip the parameter to 7 bits.
When treating them as \*(``meta\*('' keys
(or if \fBkeyname\fP is called before initializing curses),
this implementation returns strings \*(``M\-^@\*('', \*(``M\-^A\*('', etc.
+.PP
+X/Open Curses documents \fBunctrl\fP as declared in \fB<unctrl.h>\fP,
+which \fBncurses\fP does.
+However, \fBncurses\fP' \fB<curses.h>\fP includes \fB<unctrl.h>\fP,
+matching the behavior of SVr4 curses.
+Other implementations may not do that.
.SS use_env/use_tioctl
.PP
If \fBncurses\fP is configured to provide the sp-functions extension,
projects / ncurses.git / blobdiff