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Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +05301'\" t
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micky3879b9f5e72025-07-08 18:04:53 -04003.\" Copyright 2018-2023,2024 Thomas E. Dickey *
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Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +05305.\" *
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30.\"
micky3879b9f5e72025-07-08 18:04:53 -040031.\" $Id: curs_attr.3x,v 1.105 2024/04/27 17:54:42 tom Exp $
32.TH curs_attr 3X 2024-04-27 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "Library calls"
33.ie \n(.g \{\
34.ds `` \(lq
35.ds '' \(rq
36.\}
37.el \{\
38.ie t .ds `` ``
39.el .ds `` ""
40.ie t .ds '' ''
41.el .ds '' ""
42.\}
43.
44.de bP
45.ie n .IP \(bu 4
46.el .IP \(bu 2
47..
48.\" ---------------------------------------------------------------------------
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +053049.SH NAME
micky3879b9f5e72025-07-08 18:04:53 -040050\fB\%attr_get\fP,
51\fB\%wattr_get\fP,
52\fB\%attr_set\fP,
53\fB\%wattr_set\fP,
54\fB\%attr_off\fP,
55\fB\%wattr_off\fP,
56\fB\%attr_on\fP,
57\fB\%wattr_on\fP,
58\fB\%attroff\fP,
59\fB\%wattroff\fP,
60\fB\%attron\fP,
61\fB\%wattron\fP,
62\fB\%attrset\fP,
63\fB\%wattrset\fP,
64\fB\%chgat\fP,
65\fB\%wchgat\fP,
66\fB\%mvchgat\fP,
67\fB\%mvwchgat\fP,
68\fB\%color_set\fP,
69\fB\%wcolor_set\fP,
70\fB\%standend\fP,
71\fB\%wstandend\fP,
72\fB\%standout\fP,
73\fB\%wstandout\fP \-
74manipulate attributes of character cells in \fIcurses\fR windows
75.\" ---------------------------------------------------------------------------
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +053076.SH SYNOPSIS
micky3879b9f5e72025-07-08 18:04:53 -040077.nf
78\fB#include <curses.h>
79.PP
80\fBint attr_get(attr_t *\fIattrs\fP, short *\fIpair\fP, void *\fIopts\fP);
81\fBint wattr_get(WINDOW *\fIwin\fP, attr_t *\fIattrs\fP, short *\fIpair\fP,\fR \fPvoid *\fIopts\fP);
82\fBint attr_set(attr_t \fIattrs\fP, short \fIpair\fP, void *\fIopts\fP);
83\fBint wattr_set(WINDOW *\fIwin\fP, attr_t \fIattrs\fP, short \fIpair\fP, void *\fIopts\fP);
84.PP
85\fBint attr_off(attr_t \fIattrs\fP, void *\fIopts\fP);
86\fBint wattr_off(WINDOW *\fIwin\fP, attr_t \fIattrs\fP, void *\fIopts\fP);
87\fBint attr_on(attr_t \fIattrs\fP, void *\fIopts\fP);
88\fBint wattr_on(WINDOW *\fIwin\fP, attr_t \fIattrs\fP, void *\fIopts\fP);
89.PP
90\fBint attroff(int \fIattrs\fP);
91\fBint wattroff(WINDOW *\fIwin\fP, int \fIattrs\fP);
92\fBint attron(int \fIattrs\fP);
93\fBint wattron(WINDOW *\fIwin\fP, int \fIattrs\fP);
94\fBint attrset(int \fIattrs\fP);
95\fBint wattrset(WINDOW *\fIwin\fP, int \fIattrs\fP);
96.PP
97\fBint chgat(int \fIn\fP, attr_t \fIattr\fP, short \fIpair\fP,\fR \fPconst void *\fIopts\fP);
98\fBint wchgat(WINDOW *\fIwin\fP,
99 \fBint \fIn\fB, attr_t \fIattr\fB,\fR \fBshort \fIpair\fB, const void *\fIopts\fB);\fR
100\fBint mvchgat(int \fIy\fB, int \fIx\fB,\fR
101 \fBint \fIn\fB, attr_t \fIattr\fB, short \fIpair\fB, const void *\fIopts\fB);\fR
102\fBint mvwchgat(WINDOW *\fIwin\fB, int \fIy\fB, int \fIx\fB,\fR
103 \fBint \fIn\fB, attr_t \fIattr\fB, short \fIpair\fB, const void *\fIopts\fB);\fR
104.PP
105\fBint color_set(short \fIpair\fB, void* \fIopts\fB);\fR
106\fBint wcolor_set(WINDOW *\fIwin\fB, short \fIpair\fB,\fR \fBvoid* \fIopts\fP);\fR
107.PP
108\fBint standend(void);\fP
109\fBint wstandend(WINDOW *\fIwin\fB);\fR
110\fBint standout(void);\fP
111\fBint wstandout(WINDOW *\fIwin\fB);\fR
112.fi
113.\" ---------------------------------------------------------------------------
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530114.SH DESCRIPTION
micky3879b9f5e72025-07-08 18:04:53 -0400115These routines manipulate the current attributes of the named window,
116which then apply to all characters that are written into
117the window with \fBwaddch\fP, \fBwaddstr\fP and \fBwprintw\fP.
Steve Kondikae271bc2015-11-15 02:50:53 +0100118Attributes are
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530119a property of the character, and move with the character through any scrolling
Steve Kondikae271bc2015-11-15 02:50:53 +0100120and insert/delete line/character operations.
121To the extent possible, they are
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530122displayed as appropriate modifications to the graphic rendition of characters
123put on the screen.
124.PP
micky3879b9f5e72025-07-08 18:04:53 -0400125These routines do not affect the attributes used
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530126when erasing portions of the window.
micky3879b9f5e72025-07-08 18:04:53 -0400127See \fBcurs_bkgd\fP(3X) for functions which modify the attributes used for
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530128erasing and clearing.
micky3879b9f5e72025-07-08 18:04:53 -0400129.\" ---------------------------------------------------------------------------
130.SS "Window Attributes"
131There are two sets of functions:
132.bP
133functions for manipulating the window attributes and color:
134\fBwattr_set\fP and \fBwattr_get\fP.
135.bP
136functions for manipulating only the window attributes (not color):
137\fBwattr_on\fP and \fBwattr_off\fP.
138.PP
139The \fBwattr_set\fP function sets the current attributes
140of the given window to \fIattrs\fP, with color specified by \fIpair\fP.
141.PP
142Use \fBwattr_get\fP to retrieve attributes for the given window.
143.PP
144Use \fBattr_on\fP and \fBwattr_on\fP to turn on window attributes, i.e.,
145values OR'd together in \fIattr\fP,
146without affecting other attributes.
147Use \fBattr_off\fP and \fBwattr_off\fP to turn off window attributes,
148again values OR'd together in \fIattr\fP,
149without affecting other attributes.
150.\" ---------------------------------------------------------------------------
151.SS "Legacy Window Attributes"
152The X/Open window attribute routines which \fIset\fP or \fIget\fP,
153turn \fIon\fP or \fIoff\fP
154are extensions of older routines
155which assume that color pairs are OR'd into the attribute parameter.
156These newer routines use similar names, because
157X/Open simply added an underscore (\fB_\fP) for the newer names.
158.PP
159The \fBint\fP datatype used in the legacy routines is treated as if
160it is the same size as \fBchtype\fP (used by \fBaddch\fP(3X)).
161It holds the common video attributes (such as bold, reverse),
162as well as a few bits for color.
163Those bits correspond to the \fBA_COLOR\fP symbol.
164The \fBCOLOR_PAIR\fP macro provides a value which can be OR'd into
165the attribute parameter.
166For example,
167as long as that value fits into the \fBA_COLOR\fP mask,
168then these calls produce similar results:
169.PP
170.RS 4
171.EX
172attrset(A_BOLD | COLOR_PAIR(\fIpair\fP));
173attr_set(A_BOLD, \fIpair\fP, NULL);
174.EE
175.RE
176.PP
177However, if the value does not fit, then the \fBCOLOR_PAIR\fP macro
178uses only the bits that fit.
179For example,
180because in \fI\%ncurses\fP \fBA_COLOR\fP has eight (8) bits,
181then \fBCOLOR_PAIR(\fI259\fB)\fR is 4
182(i.e., 259 is 4 more than the limit 255).
183.PP
184The \fBPAIR_NUMBER\fP macro extracts a pair number from an \fBint\fP
185(or \fBchtype\fP).
186For example, the \fIinput\fP and \fIoutput\fP values in these statements
187would be the same:
188.PP
189.RS 4
190.EX
191int value = A_BOLD | COLOR_PAIR(\fIinput\fP);
192int \fIoutput\fP = PAIR_NUMBER(value);
193.EE
194.RE
195.PP
196The \fBattrset\fP routine is a legacy feature predating SVr4 curses
Steve Kondikae271bc2015-11-15 02:50:53 +0100197but kept in X/Open Curses for the same reason that SVr4 curses kept it:
micky3879b9f5e72025-07-08 18:04:53 -0400198compatibility.
Steve Kondikae271bc2015-11-15 02:50:53 +0100199.PP
micky3879b9f5e72025-07-08 18:04:53 -0400200The remaining \fBattr\fP* functions operate exactly like the corresponding
201\fBattr_\fP* functions, except that they take arguments of type \fBint\fP
202rather than \fBattr_t\fP.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530203.PP
micky3879b9f5e72025-07-08 18:04:53 -0400204There is no corresponding \fB\%attrget\fP function as such
205in X/Open Curses,
206although \fI\%ncurses\fP provides \fB\%getattrs\fP
207(see \fB\%curs_legacy\fP(3X)).
208.\" ---------------------------------------------------------------------------
209.SS "Change Character Rendition"
210The routine \fBchgat\fP changes the attributes of a given number of characters
211starting at the current cursor location of \fBstdscr\fP.
Steve Kondikae271bc2015-11-15 02:50:53 +0100212It does not update
213the cursor and does not perform wrapping.
214A character count of \-1 or greater
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530215than the remaining window width means to change attributes all the way to the
Steve Kondikae271bc2015-11-15 02:50:53 +0100216end of the current line.
micky3879b9f5e72025-07-08 18:04:53 -0400217The \fBwchgat\fP function generalizes this to any window;
218the \fBmvwchgat\fP function does a cursor move before acting.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530219.PP
micky3879b9f5e72025-07-08 18:04:53 -0400220In these functions,
221the color \fIpair\fP argument is a color pair index
222(as in the first argument of \fBinit_pair\fP, see \fBcurs_color\fP(3X)).
223.\" ---------------------------------------------------------------------------
224.SS "Change Window Color"
225The routine \fBcolor_set\fP sets the current color of the given window to the
226foreground/background combination described by the color \fIpair\fP parameter.
227.\" ---------------------------------------------------------------------------
228.SS Standout
229The routine \fBstandout\fP is
230the same as \fBattron(A_STANDOUT)\fP.
231The routine \fBstandend\fP is the same
232as \fBattrset(A_NORMAL)\fP or \fBattrset(0)\fP, that is, it turns off all
233attributes.
234.PP
235X/Open Curses does not mark these \*(``restricted\*('', because
236.bP
237they have well established legacy use, and
238.bP
239there is no ambiguity about the way the attributes
240might be combined with a color pair.
241.\" ---------------------------------------------------------------------------
242.SS "Video Attributes"
243The following video attributes, defined in \fB<curses.h>\fP, can be passed to
244the routines \fBattron\fP, \fBattroff\fP, and \fBattrset\fP, or OR'd with the
245characters passed to \fBaddch\fP (see \fBcurs_addch\fP(3X)).
246.PP
247.ne 15
Steve Kondikae271bc2015-11-15 02:50:53 +0100248.RS
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530249.TS
micky3879b9f5e72025-07-08 18:04:53 -0400250Lb Lb
251Lb Lx.
252Name Description
253_
254A_NORMAL Normal display (no highlight)
255A_STANDOUT T{
256Best highlighting mode of the terminal
257T}
258A_UNDERLINE Underlining
259A_REVERSE Reverse video
260A_BLINK Blinking
261A_DIM Half bright
262A_BOLD Extra bright or bold
263A_PROTECT Protected mode
264A_INVIS Invisible or blank mode
265A_ALTCHARSET Alternate character set
266A_ITALIC Italics (non-X/Open extension)
267A_CHARTEXT Bit-mask to extract a character
268A_COLOR T{
269Bit-mask to extract a color (legacy routines)
270T}
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530271.TE
Steve Kondikae271bc2015-11-15 02:50:53 +0100272.RE
273.PP
274These video attributes are supported by \fBattr_on\fP and related functions
275(which also support the attributes recognized by \fBattron\fP, etc.):
micky3879b9f5e72025-07-08 18:04:53 -0400276.PP
Steve Kondikae271bc2015-11-15 02:50:53 +0100277.RS
278.TS
micky3879b9f5e72025-07-08 18:04:53 -0400279Lb Lb
280Lb Lx.
281Name Description
282_
283WA_HORIZONTAL Horizontal highlight
284WA_LEFT Left highlight
285WA_LOW Low highlight
286WA_RIGHT Right highlight
287WA_TOP Top highlight
288WA_VERTICAL Vertical highlight
Steve Kondikae271bc2015-11-15 02:50:53 +0100289.TE
290.RE
291.PP
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530292The return values of many of these routines are not meaningful (they are
293implemented as macro-expanded assignments and simply return their argument).
micky3879b9f5e72025-07-08 18:04:53 -0400294The SVr4 manual page claims (falsely) that these routines always return \fB1\fP.
295.\" ---------------------------------------------------------------------------
296.SH RETURN VALUE
297All routines return the integer \fBOK\fP on success, or \fBERR\fP on failure.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530298.PP
micky3879b9f5e72025-07-08 18:04:53 -0400299X/Open Curses does not specify any error conditions.
300.PP
301This implementation
302.bP
303returns an error if the window pointer is null.
304.bP
305returns an error if the color pair parameter
306for \fBwcolor_set\fP is outside the range 0..COLOR_PAIRS\-1.
307.bP
308does not return an error if either of the parameters of \fBwattr_get\fP
309used for retrieving attribute or color pair values is \fBNULL\fP.
310.PP
311Functions prefixed with \*(``mv\*('' first perform cursor movement and
312fail if the position
313.RI ( y ,
314.IR x )
315is outside the window boundaries.
316.\" ---------------------------------------------------------------------------
317.SH NOTES
318These functions may be macros:
319.sp
320.RS
321\fBattroff\fP, \fBwattroff\fP, \fBattron\fP, \fBwattron\fP,
322\fBattrset\fP, \fBwattrset\fP, \fBstandend\fP and \fBstandout\fP.
323.RE
324.PP
325Color pair values can only be OR'd with attributes if the pair
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530326number is less than 256.
327The alternate functions such as \fBcolor_set\fP can pass a color pair
328value directly.
micky3879b9f5e72025-07-08 18:04:53 -0400329However, \fI\%ncurses\fP ABI 4 and 5 simply OR this value
330within the alternate functions.
331You must use \fI\%ncurses\fP ABI 6 to support more than 256 color pairs.
332.\" ---------------------------------------------------------------------------
333.SH EXTENSIONS
334This implementation provides the \fBA_ITALIC\fP attribute for terminals
335which have the \fBenter_italics_mode\fP (\fBsitm\fP)
336and \fBexit_italics_mode\fP (\fBritm\fP) capabilities.
337Italics are not mentioned in X/Open Curses.
338Unlike the other video attributes, \fBA_ITALIC\fP is unrelated
339to the \fBset_attributes\fP capabilities.
340This implementation makes the assumption that
341\fBexit_attribute_mode\fP may also reset italics.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530342.PP
micky3879b9f5e72025-07-08 18:04:53 -0400343Each of the functions added by XSI Curses has a parameter \fIopts\fP,
344which X/Open Curses still (after more than twenty years) documents
345as reserved for future use, saying that it should be \fBNULL\fP.
346This implementation uses that parameter in ABI 6 for the functions which
347have a color pair parameter to support \fIextended color pairs\fP:
348.bP
349For functions which modify the color, e.g.,
350\fBwattr_set\fP and \fBwattr_on\fP,
351if \fIopts\fP is set it is treated as a pointer to \fBint\fP,
352and used to set the color pair instead of the \fBshort\fP \fIpair\fP parameter.
353.bP
354For functions which retrieve the color, e.g.,
355\fBwattr_get\fP,
356if \fIopts\fP is set it is treated as a pointer to \fBint\fP,
357and used to retrieve the color pair as an \fBint\fP value,
358in addition to
359retrieving it via the standard pointer to \fBshort\fP parameter.
360.bP
361For functions which turn attributes off, e.g.,
362\fBwattr_off\fP,
363the \fIopts\fP parameter is ignored except
364except to check that it is \fBNULL\fP.
365.\" ---------------------------------------------------------------------------
366.SH PORTABILITY
367These functions are described in X/Open Curses, Issue 4.
368The standard defined the dedicated type for highlights,
369\fBattr_t\fP, which was not defined in SVr4 curses.
370The functions taking \fBattr_t\fP arguments were not supported under SVr4.
371.PP
372Very old versions of this library did not force an update of the screen
373when changing the attributes.
374Use \fBtouchwin\fP to force the screen to match the updated attributes.
375.PP
376X/Open Curses states that whether the traditional functions
377\fBattron\fP/\fBattroff\fP/\fBattrset\fP can manipulate attributes other than
378\fBA_BLINK\fP, \fBA_BOLD\fP, \fBA_DIM\fP, \fBA_REVERSE\fP, \fBA_STANDOUT\fP, or
379\fBA_UNDERLINE\fP is \*(``unspecified\*(''.
Steve Kondikae271bc2015-11-15 02:50:53 +0100380Under this implementation as well as
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530381SVr4 curses, these functions correctly manipulate all other highlights
micky3879b9f5e72025-07-08 18:04:53 -0400382(specifically, \fBA_ALTCHARSET\fP, \fBA_PROTECT\fP, and \fBA_INVIS\fP).
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530383.PP
micky3879b9f5e72025-07-08 18:04:53 -0400384X/Open Curses added these entry points:
385.sp
386.RS
387\fBattr_get\fP, \fBattr_on\fP,
388\fBattr_off\fP, \fBattr_set\fP, \fBwattr_on\fP, \fBwattr_off\fP,
389\fBwattr_get\fP, \fBwattr_set\fP
390.RE
Steve Kondikae271bc2015-11-15 02:50:53 +0100391.PP
micky3879b9f5e72025-07-08 18:04:53 -0400392The new functions are intended to work with
393a new series of highlight macros prefixed with \fBWA_\fP.
Steve Kondikae271bc2015-11-15 02:50:53 +0100394The older macros have direct counterparts in the newer set of names:
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530395.PP
Steve Kondikae271bc2015-11-15 02:50:53 +0100396.RS
397.ne 9
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530398.TS
micky3879b9f5e72025-07-08 18:04:53 -0400399Lb Lb
400Lb Lx.
401Name Description
402_
403WA_NORMAL Normal display (no highlight)
404WA_STANDOUT T{
405Best highlighting mode of the terminal
406T}
407WA_UNDERLINE Underlining
408WA_REVERSE Reverse video
409WA_BLINK Blinking
410WA_DIM Half bright
411WA_BOLD Extra bright or bold
412WA_ALTCHARSET Alternate character set
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530413.TE
Steve Kondikae271bc2015-11-15 02:50:53 +0100414.RE
415.PP
micky3879b9f5e72025-07-08 18:04:53 -0400416X/Open Curses does not assign values to these symbols,
417nor does it state whether or not they are related to the
418similarly-named A_NORMAL, etc.:
419.bP
420X/Open Curses specifies that each pair of corresponding \fBA_\fP
421and \fBWA_\fP-using functions operates on the same current-highlight
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530422information.
micky3879b9f5e72025-07-08 18:04:53 -0400423.bP
424However, in some implementations, those symbols have unrelated values.
425.IP
426For example, the Solaris \fIxpg4\fP (X/Open) curses declares
427\fBattr_t\fP to be an unsigned short integer (16-bits),
428while \fBchtype\fP is a unsigned integer (32-bits).
429The \fBWA_\fP symbols in this case are different from the \fBA_\fP symbols
430because they are used for a smaller datatype which does not
431represent \fBA_CHARTEXT\fP or \fBA_COLOR\fP.
432.IP
433In this implementation (as in many others), the values happen to be
434the same because it simplifies copying information between
435\fBchtype\fP and \fBcchar_t\fP variables.
436.bP
437Because \fI\%ncurses\fP's \fBattr_t\fP can hold a color pair
438(in the \fBA_COLOR\fP field),
439a call to
440\fBwattr_on\fP,
441\fBwattr_off\fP, or
442\fBwattr_set\fP
443may alter the window's color.
444If the color pair information in the attribute parameter is zero,
445no change is made to the window's color.
446.IP
447This is consistent with SVr4 curses;
448X/Open Curses does not specify this.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530449.PP
micky3879b9f5e72025-07-08 18:04:53 -0400450The X/Open Curses extended conformance level adds new highlights
451\fBA_HORIZONTAL\fP, \fBA_LEFT\fP, \fBA_LOW\fP, \fBA_RIGHT\fP, \fBA_TOP\fP,
452\fBA_VERTICAL\fP (and corresponding \fBWA_\fP macros for each).
Steve Kondikae271bc2015-11-15 02:50:53 +0100453As of August 2013,
454no known terminal provides these highlights
455(i.e., via the \fBsgr1\fP capability).
micky3879b9f5e72025-07-08 18:04:53 -0400456.\" ---------------------------------------------------------------------------
457.SH HISTORY
458X/Open Curses is largely based on SVr4 curses,
459adding support for \*(``wide-characters\*('' (not specific to Unicode).
460Some of the X/Open differences from SVr4 curses address the way
461video attributes can be applied to wide-characters.
462But aside from that, \fBattrset\fP and \fBattr_set\fP are similar.
463SVr4 curses provided the basic features for manipulating video attributes.
464However, earlier versions of curses provided a part of these features.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530465.PP
micky3879b9f5e72025-07-08 18:04:53 -0400466As seen in 2.8BSD, curses assumed 7-bit characters,
467using the eighth bit of a byte to represent the \fIstandout\fP
468feature (often implemented as bold and/or reverse video).
469The BSD curses library provided functions \fBstandout\fP and \fBstandend\fP
470which were carried along into X/Open Curses due to their pervasive use
471in legacy applications.
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530472.PP
micky3879b9f5e72025-07-08 18:04:53 -0400473Some terminals in the 1980s could support a variety of video attributes,
474although the BSD curses library could do nothing with those.
475System V (1983) provided an improved curses library.
476It defined the \fBA_\fP symbols for use by applications to manipulate the
477other attributes.
478There are few useful references for the chronology.
Steve Kondikae271bc2015-11-15 02:50:53 +0100479.PP
micky3879b9f5e72025-07-08 18:04:53 -0400480Goodheart's book
481\fIUNIX Curses Explained\fP (1991) describes SVr3 (1987),
482commenting on several functions:
483.bP
484the \fBattron\fP, \fBattroff\fP, \fBattrset\fP functions
485(and most of the functions found in SVr4 but not in BSD curses) were
486introduced by System V,
487.bP
488the alternate character set feature with \fBA_ALTCHARSET\fP was
489added in SVr2 and improved in SVr3 (by adding \fBacs_map[]\fP),
490.bP
491\fBstart_color\fP and related color-functions were introduced by System V.3.2,
492.bP
493pads, soft-keys were added in SVr3, and
494.PP
495Goodheart did not mention the background character or the \fBcchar_t\fP type.
496Those are respectively SVr4 and X/Open features.
497He did mention the \fBA_\fP constants, but did not indicate their values.
498Those were not the same in different systems,
499even for those marked as System V.
500.PP
501Different Unix systems used different sizes for the bit-fields in \fBchtype\fP
502for \fIcharacters\fP and \fIcolors\fP, and took into account the different
503integer sizes (32-bit versus 64-bit).
504.PP
505This table showing the number of bits for \fBA_COLOR\fP
506and \fBA_CHARTEXT\fP
507was gleaned from the curses header files for
508various operating systems and architectures.
509The inferred architecture and notes reflect
510the format and size of the defined constants
511as well as clues such as the alternate character set implementation.
512A 32-bit library can be used on a 64-bit system,
513but not necessarily the reverse.
514.PP
515.TS
516Lb Lb Lb Cb S Lb
517Lb2 Lb Lb2 Lb2 Lb2 Lb
518L L L L L Lx.
519\& \& \& Bits \&
520Year System Arch Color Char Notes
521_
5221992 Solaris 5.2 32 6 17 SVr4 \fIcurses\fP
5231992 HP-UX 9 32 no 8 SVr2 \fIcurses\fP
5241992 AIX 3.2 32 no 23 SVr2 \fIcurses\fP
5251994 OSF/1 r3 32 no 23 SVr2 \fIcurses\fP
5261995 HP-UX 10.00 32 6 16 SVr3 \fIcurses_colr\fP
5271995 HP-UX 10.00 32 6 8 SVr4, X/Open \fIcurses\fP
5281995 Solaris 5.4 32/64 7 16 X/Open \fIcurses\fP
5291996 AIX 4.2 32 7 16 X/Open \fIcurses\fP
5301996 OSF/1 r4 32 6 16 X/Open \fIcurses\fP
5311997 HP-UX 11.00 32 6 8 X/Open \fIcurses\fP
5322000 U/Win 32/64 7/31 16 uses \fIchtype\fP
533.TE
534.PP
535Notes:
536.RS 3
537.PP
538Regarding HP-UX,
539.bP
540HP-UX 10.20 (1996) added support for 64-bit PA-RISC processors in 1996.
541.bP
542HP-UX 10.30 (1997) marked \*(``curses_colr\*('' obsolete.
543That version of curses was dropped with HP-UX 11.30 in 2006.
544.PP
545Regarding OSF/1 (and Tru64),
546.bP
547These used 64-bit hardware.
548Like \fI\%ncurses\fP,
549the OSF/1 curses interface is not customized for 32-bit and 64-bit
550versions.
551.bP
552Unlike other systems which evolved from AT&T code,
553OSF/1 provided a new implementation for X/Open curses.
554.PP
555Regarding Solaris,
556.bP
557The initial release of Solaris was in 1992.
558.bP
559The \fIxpg4\fP (X/Open) curses was developed by MKS from 1990 to 1995.
560Sun's copyright began in 1996.
561.bP
562Sun updated the X/Open curses interface
563after 64-bit support was introduced in 1997,
564but did not modify the SVr4 curses interface.
565.PP
566Regarding U/Win,
567.bP
568Development of the curses library began in 1991, stopped in 2000.
569.bP
570Color support was added in 1998.
571.bP
572The library uses only \fBchtype\fP (no \fBcchar_t\fP).
573.RE
574.PP
575Once X/Open curses was adopted in the mid-1990s, the constraint of
576a 32-bit interface with many colors and wide-characters for \fBchtype\fP
577became a moot point.
578The \fBcchar_t\fP structure (whose size and
579members are not specified in X/Open Curses) could be extended as needed.
580.PP
581Other interfaces are rarely used now:
582.bP
583BSD curses was improved slightly in 1993/1994 using Keith Bostic's
584modification to make the library 8-bit clean for \fBnvi\fP(1).
585He moved \fIstandout\fP attribute to a structure member.
586.IP
587The resulting 4.4BSD curses was replaced by \fI\%ncurses\fP over the
588next ten years.
589.bP
590U/Win is rarely used now.
591.\" ---------------------------------------------------------------------------
Amit Daniel Kachhape6a01f52011-07-20 11:45:59 +0530592.SH SEE ALSO
micky3879b9f5e72025-07-08 18:04:53 -0400593\fB\%curses\fP(3X),
594\fB\%curs_addch\fP(3X),
595\fB\%curs_addstr\fP(3X),
596\fB\%curs_bkgd\fP(3X),
597\fB\%curs_printw\fP(3X),
598\fB\%curs_variables\fP(3X)