X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=man%2Fcurs_getcchar.3x;h=cc127e226c7ae9160387810f8a57f08c0349d769;hp=1b878f313c2dc84b58e5c189d6ae97ddf7aba8e4;hb=HEAD;hpb=96d6b16de0d487e5d3aed0302a179dbce11b5d96 diff --git a/man/curs_getcchar.3x b/man/curs_getcchar.3x index 1b878f31..523cc99d 100644 --- a/man/curs_getcchar.3x +++ b/man/curs_getcchar.3x @@ -1,5 +1,6 @@ .\"*************************************************************************** -.\" Copyright (c) 2001-2009,2010 Free Software Foundation, Inc. * +.\" Copyright 2019-2023,2024 Thomas E. Dickey * +.\" Copyright 2001-2015,2017 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 * @@ -26,70 +27,64 @@ .\" authorization. * .\"*************************************************************************** .\" -.\" $Id: curs_getcchar.3x,v 1.15 2010/12/04 18:36:44 tom Exp $ -.TH curs_getcchar 3X "" +.\" $Id: curs_getcchar.3x,v 1.49 2024/04/20 18:55:09 tom Exp $ +.TH curs_getcchar 3X 2024-04-20 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls" .de bP -.IP \(bu 4 +.ie n .IP \(bu 4 +.el .IP \(bu 2 .. .SH NAME -\fBgetcchar\fP, -\fBsetcchar\fP \- Get a wide character string and rendition from a \fBcchar_t\fP or set a \fBcchar_t\fP from a wide-character string +\fB\%getcchar\fP, +\fB\%setcchar\fP \- +convert between a wide-character string and a \fIcurses\fR complex character .SH SYNOPSIS -\fB#include \fP -.sp -\fBint getcchar(\fP -.br -.B " const cchar_t *\fIwcval\fP," -.br -.B " wchar_t *\fIwch\fP," -.br +.nf +\fB#include +.PP +\fBint getcchar( +.B " const cchar_t *\fIwch\fP," +.B " wchar_t *\fIwc\fP," .B " attr_t *\fIattrs\fP," -.br .B " short *\fIcolor_pair\fP," -.br .B " void *\fIopts\fP );" -.sp +.PP .B "int setcchar(" -.br -.B " cchar_t *\fIwcval\fP," -.br -.B " const wchar_t *\fIwch\fP," -.br +.B " cchar_t *\fIwch\fP," +.B " const wchar_t *\fIwc\fP," .B " const attr_t \fIattrs\fP," -.br .B " short \fIcolor_pair\fP," -.br -.B " void *\fIopts\fP );" +.B " const void *\fIopts\fP );" +.fi .SH DESCRIPTION -.PP +.SS getcchar The \fBgetcchar\fP function gets a wide-character string and rendition from a \fBcchar_t\fP argument. -When \fIwch\fP is not a null pointer, +When \fIwc\fP is not a null pointer, the \fBgetcchar\fP function does the following: .bP -Extracts information from a \fBcchar_t\fP value \fIwcval\fP +Extracts information from a \fBcchar_t\fP value \fIwch\fP .bP Stores the character attributes in the location pointed to by \fIattrs\fP .bP -Stores the color-pair in the location pointed to by \fIcolor_pair\fP +Stores the color pair in the location pointed to by \fIcolor_pair\fP .bP Stores the wide-character string, -characters referenced by \fIwcval\fP, into the array pointed to by \fIwch\fP. +characters referenced by \fIwch\fP, into the array pointed to by \fIwc\fP. .PP When -\fIwch\fP +\fIwc\fP is a null pointer, the \fBgetcchar\fP function does the following: .bP -Obtains the number of wide characters pointed to by \fIwcval\fP +Obtains the number of wide characters pointed to by \fIwch\fP .bP Does not change the data referenced by \fIattrs\fP or \fIcolor_pair\fP -.PP -The \fBsetcchar\fP function initializes the location pointed to by \fIwcval\fP +.SS setcchar +The \fBsetcchar\fP function initializes the location pointed to by \fIwch\fP by using: .bP The character attributes in @@ -98,41 +93,96 @@ The character attributes in The color pair in \fIcolor_pair\fP .bP -The wide-character string pointed to by \fIwch\fP. -The string must be L'\\0' terminated, +The wide-character string pointed to by \fIwc\fP. +The string must be L'\e0' terminated, contain at most one spacing character, which must be the first. .IP -Up to \fBCCHARW_MAX\fP\-1 nonspacing characters may follow. -Additional nonspacing characters are ignored. +Up to \fBCCHARW_MAX\fP\-1 non-spacing characters may follow. +Additional non-spacing characters are ignored. .IP The string may contain a single control character instead. -In that case, no nonspacing characters are allowed. -.SH NOTES -.PP -The \fIopts\fP argument is reserved for future use. -Currently, an application must provide a null pointer as \fIopts\fP. -.PP -The \fIwcval\fP argument may be a value generated by a call to -\fBsetcchar\fP or by a function that has a \fBcchar_t\fP output argument. -If \fIwcval\fP is constructed by any other means, the effect is unspecified. -.SH RETURN VALUES -.PP -When \fIwch\fP is a null pointer, +In that case, no non-spacing characters are allowed. +.SH RETURN VALUE +When \fIwc\fP is a null pointer, \fBgetcchar\fP returns the number of wide characters referenced by -\fIwcval\fP, +\fIwch\fP, including one for a trailing null. .PP -When \fIwch\fP is not a null pointer, +When \fIwc\fP is not a null pointer, \fBgetcchar\fP returns \fBOK\fP upon successful completion, and \fBERR\fP otherwise. .PP Upon successful completion, \fBsetcchar\fP returns \fBOK\fP. Otherwise, it returns \fBERR\fP. -.SH SEE ALSO +.SH NOTES +The \fIwch\fP argument may be a value generated by a call to +\fBsetcchar\fP or by a function that has a \fBcchar_t\fP output argument. +If \fIwch\fP is constructed by any other means, the effect is unspecified. +.SH EXTENSIONS +X/Open Curses documents the \fIopts\fP argument as reserved for future use, +saying that it must be null. +This implementation +uses that parameter in ABI 6 for the functions which have a color pair +parameter to support extended color pairs: +.bP +For functions which modify the color, e.g., \fBsetcchar\fP, +if \fIopts\fP is set it is treated as a pointer to \fBint\fP, +and used to set the color pair instead of the \fBshort\fP pair parameter. +.bP +For functions which retrieve the color, e.g., \fBgetcchar\fP, +if \fIopts\fP is set it is treated as a pointer to \fBint\fP, +and used to retrieve the color pair as an \fBint\fP value, +in addition retrieving it via the standard pointer to \fBshort\fP parameter. +.SH PORTABILITY +The \fBCCHARW_MAX\fP symbol is specific to \fI\%ncurses\fP. +X/Open Curses does not provide details for the layout of the \fBcchar_t\fP +structure. +It tells what data are stored in it: +.bP +a spacing character (\fBwchar_t\fP, i.e., 32-bits). +.bP +non-spacing characters (again, \fBwchar_t\fP's). +.bP +attributes (at least 16 bits, inferred from the various ACS- and WACS-flags). +.bP +color pair (at least 16 bits, inferred from the \fBunsigned short\fP type). +.PP +The non-spacing characters are optional, +in the sense that zero or more may be stored in a \fBcchar_t\fP. +XOpen/Curses specifies a limit: +.RS 4 +.PP +Implementations may limit the number of non-spacing characters that can be +associated with a spacing character, provided any limit is at least 5. +.RE .PP -Functions: -\fBcurs_attr\fR(3X), -\fBcurs_color\fR(3X), -\fBcurses\fR(3X), -\fBwcwidth\fR(3). +The Unix implementations at the time follow that limit: +.bP +AIX\ 4 and OSF1\ 4 use the same declaration with an array of 5 non-spacing +characters \fIz\fP and a single spacing character \fIc\fP. +.bP +HP-UX\ 10 uses an opaque structure with 28 bytes, +which is large enough for the 6 \fBwchar_t\fP values. +.bP +Solaris \fIxpg4\fP curses uses a single array of 6 \fBwchar_t\fP values. +.PP +This implementation's \fBcchar_t\fP was defined in 1995 +using \fB5\fP for the total of spacing and non-spacing characters +(\fBCCHARW_MAX\fP). +That was probably due to a misreading of the AIX\ 4 header files, +because the X/Open Curses document was not generally available at that time. +Later (in 2002), this detail was overlooked when beginning to implement +the functions using the structure. +.PP +In practice, even four non-spacing characters may seem enough. +X/Open Curses documents possible uses for non-spacing characters, +including using them for ligatures between characters +(a feature apparently not supported by any curses implementation). +Unicode does not limit the (analogous) number of combining characters, +so some applications may be affected. +.SH SEE ALSO +\fB\%curses\fP(3X), +\fB\%curs_attr\fP(3X), +\fB\%curs_color\fP(3X), +\fB\%wcwidth\fP(3)