| <!-- |
| **************************************************************************** |
| * Copyright 2018-2023,2024 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 * |
| * "Software"), to deal in the Software without restriction, including * |
| * without limitation the rights to use, copy, modify, merge, publish, * |
| * distribute, distribute with modifications, sublicense, and/or sell * |
| * copies of the Software, and to permit persons to whom the Software is * |
| * furnished to do so, subject to the following conditions: * |
| * * |
| * The above copyright notice and this permission notice shall be included * |
| * in all copies or substantial portions of the Software. * |
| * * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * |
| * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * |
| * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * |
| * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * |
| * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * |
| * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * |
| * * |
| * Except as contained in this notice, the name(s) of the above copyright * |
| * holders shall not be used in advertising or otherwise to promote the * |
| * sale, use or other dealings in this Software without prior written * |
| * authorization. * |
| **************************************************************************** |
| * @Id: curs_pad.3x,v 1.61 2024/04/27 17:55:43 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_pad 3x 2024-04-27 ncurses 6.5 Library calls</TITLE> |
| <link rel="author" href="mailto:bug-ncurses@gnu.org"> |
| |
| </HEAD> |
| <BODY> |
| <H1 class="no-header">curs_pad 3x 2024-04-27 ncurses 6.5 Library calls</H1> |
| <PRE> |
| <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG> |
| |
| |
| |
| |
| </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE> |
| <STRONG>newpad</STRONG>, <STRONG>subpad</STRONG>, <STRONG>prefresh</STRONG>, <STRONG>pnoutrefresh</STRONG>, <STRONG>pechochar</STRONG>, <STRONG>pecho_wchar</STRONG> - create |
| and display <EM>curses</EM> pads |
| |
| |
| </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE> |
| <STRONG>#include</STRONG> <STRONG><curses.h></STRONG> |
| |
| <STRONG>WINDOW</STRONG> <STRONG>*newpad(int</STRONG> <EM>nlines</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>ncols</EM><STRONG>);</STRONG> |
| <STRONG>WINDOW</STRONG> <STRONG>*subpad(WINDOW</STRONG> <STRONG>*</STRONG><EM>parent</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>nlines</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>ncols</EM><STRONG>,</STRONG> |
| <STRONG>int</STRONG> <EM>begin</EM><STRONG>_</STRONG><EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>begin</EM><STRONG>_</STRONG><EM>x</EM><STRONG>);</STRONG> |
| |
| <STRONG>int</STRONG> <STRONG>prefresh(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pmincol</EM><STRONG>,</STRONG> |
| <STRONG>int</STRONG> <EM>sminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smincol</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxcol</EM><STRONG>);</STRONG> |
| <STRONG>int</STRONG> <STRONG>pnoutrefresh(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>pmincol</EM><STRONG>,</STRONG> |
| <STRONG>int</STRONG> <EM>sminrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smincol</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxrow</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>smaxcol</EM><STRONG>);</STRONG> |
| |
| <STRONG>int</STRONG> <STRONG>pechochar(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>chtype</STRONG> <EM>ch</EM><STRONG>);</STRONG> |
| <STRONG>int</STRONG> <STRONG>pecho_wchar(WINDOW</STRONG> <STRONG>*</STRONG><EM>pad</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM><STRONG>);</STRONG> |
| |
| |
| </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE> |
| A <EM>curses</EM> <EM>pad</EM> is like a window, except that it is not restricted by the |
| screen size, and is not necessarily associated with a particular part |
| of the screen. Pads can be used when a large window is needed, only |
| part of which is to be visible on the screen. Pads are not |
| automatically refreshed by scrolling or input-echoing operations. |
| |
| Pads cannot be refreshed with <STRONG><A HREF="curs_refresh.3x.html">wrefresh(3x)</A></STRONG>; use <STRONG>prefresh</STRONG> or |
| <STRONG>pnoutrefresh</STRONG> instead. |
| |
| |
| </PRE><H3><a name="h3-newpad">newpad</a></H3><PRE> |
| <STRONG>newpad</STRONG> creates and returns a pointer to a new pad data structure with |
| the given number of lines, <EM>nlines</EM>, and columns, <EM>ncols</EM>. |
| |
| |
| </PRE><H3><a name="h3-subpad">subpad</a></H3><PRE> |
| <STRONG>subpad</STRONG> creates and returns a pointer to a subwindow within a pad with |
| the given number of lines, <EM>nlines</EM>, and columns, <EM>ncols</EM>. Unlike |
| <STRONG><A HREF="subwin.3x.html">subwin(3x)</A></STRONG>, which uses screen coordinates, the new pad is placed at |
| position (<EM>begin</EM><STRONG>_</STRONG><EM>y</EM>, <EM>begin</EM><STRONG>_</STRONG><EM>x</EM>) relative to its parent. Thus, changes made |
| to one pad can affect both. When operating on a subpad, it is often |
| necessary to call <STRONG><A HREF="curs_touch.3x.html">touchwin(3x)</A></STRONG> or <STRONG><A HREF="curs_touch.3x.html">touchline(3x)</A></STRONG> on <EM>parent</EM> before |
| calling <STRONG>prefresh</STRONG>. |
| |
| |
| </PRE><H3><a name="h3-prefresh_pnoutrefresh">prefresh, pnoutrefresh</a></H3><PRE> |
| <STRONG>prefresh</STRONG> and <STRONG>pnoutrefresh</STRONG> are analogous to <STRONG><A HREF="curs_refresh.3x.html">wrefresh(3x)</A></STRONG> and |
| <STRONG><A HREF="curs_refresh.3x.html">wnoutrefresh(3x)</A></STRONG> except that they operate on pads rather than windows. |
| They require additional parameters are needed to indicate what portions |
| of the pad and screen are involved. |
| |
| <STRONG>o</STRONG> <EM>pminrow</EM> and <EM>pmincol</EM> specify the upper left-hand corner of a |
| rectangular view of the pad. |
| |
| <STRONG>o</STRONG> <EM>sminrow</EM>, <EM>smincol</EM>, <EM>smaxrow</EM>, and <EM>smaxcol</EM> specify the vertices of the |
| rectangle to be displayed on the screen. |
| |
| The lower right-hand corner of the rectangle to be displayed in the pad |
| is calculated from the screen coordinates, since the rectangles must be |
| the same size. Both rectangles must be entirely contained within their |
| respective structures. <EM>curses</EM> treats negative values of any of these |
| parameters as zero. |
| |
| |
| </PRE><H3><a name="h3-pechochar">pechochar</a></H3><PRE> |
| <STRONG>pechochar</STRONG> is functionally equivalent to calling <STRONG><A HREF="curs_addch.3x.html">waddch(3x)</A></STRONG> followed by |
| <STRONG>prefresh</STRONG>. It suggests to the <EM>curses</EM> optimizer that only a single |
| character is being output; a considerable performance benefit may be |
| thus enjoyed. The location of the character <EM>ch</EM> written to the pad is |
| used to populate the arguments to <STRONG>prefresh</STRONG>. |
| |
| |
| </PRE><H3><a name="h3-pecho_wchar">pecho_wchar</a></H3><PRE> |
| <STRONG>pecho_wchar</STRONG> is functionally equivalent to calling <STRONG><A HREF="curs_add_wch.3x.html">wadd_wch(3x)</A></STRONG> followed |
| by <STRONG>prefresh</STRONG>. It suggests to the <EM>curses</EM> optimizer that only a single |
| wide character is being output; a considerable performance benefit may |
| be thus enjoyed. The location of the character <EM>wch</EM> written to the pad |
| is used to populate the arguments to <STRONG>prefresh</STRONG>. |
| |
| |
| </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE> |
| Functions that return an integer return <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> (SVr4 |
| specifies only "an integer value other than <STRONG>ERR</STRONG>") upon successful |
| completion. |
| |
| Functions that return pointers return <STRONG>NULL</STRONG> on error, and set <STRONG>errno</STRONG> to |
| <STRONG>ENOMEM</STRONG>. |
| |
| X/Open Curses does not specify any error conditions. In this |
| implementation |
| |
| <STRONG>prefresh</STRONG> and <STRONG>pnoutrefresh</STRONG> |
| return an error if the window pointer is null, or if the window |
| is not really a pad or if the area to refresh extends off- |
| screen or if the minimum coordinates are greater than the |
| maximum. |
| |
| <STRONG>pechochar</STRONG> |
| returns an error if the window is not really a pad, and the |
| associated call to <STRONG>wechochar</STRONG> returns an error. |
| |
| <STRONG>pecho_wchar</STRONG> |
| returns an error if the window is not really a pad, and the |
| associated call to <STRONG>wecho_wchar</STRONG> returns an error. |
| |
| |
| </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE> |
| <STRONG>pechochar</STRONG> may be a macro. |
| |
| |
| </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE> |
| BSD <EM>curses</EM> has no <EM>pad</EM> feature. |
| |
| SVr2 <EM>curses</EM> (1986) provided the <STRONG>newpad</STRONG> and related functions, |
| documenting them in a single line each. SVr3 (1987) provided more |
| extensive documentation. |
| |
| The documentation does not explain the term <EM>pad</EM>. However, the Apollo |
| <EM>Aegis</EM> workstation operating system supported a graphical <EM>pad</EM> feature: |
| |
| <STRONG>o</STRONG> These graphical pads could be much larger than the computer's |
| display. |
| |
| <STRONG>o</STRONG> The read-only output from a command could be scrolled back to |
| inspect, and select text from the pad. |
| |
| The two uses may be related. |
| |
| X/Open Curses, Issue 4 describes these functions, without significant |
| change from the SVr3 documentation. It describes no error conditions. |
| The behavior of <STRONG>subpad</STRONG> if the parent window is not a pad is |
| undocumented, and is not checked by the vendor Unix implementations: |
| |
| <STRONG>o</STRONG> SVr4 <EM>curses</EM> sets a flag in the <EM>WINDOW</EM> structure in <STRONG>newpad</STRONG> which |
| tells if the window is a <EM>pad</EM>. |
| |
| However, it uses this information only in <STRONG>waddch</STRONG> (to decide if it |
| should call <STRONG>wrefresh</STRONG>) and <STRONG>wscrl</STRONG> (to avoid scrolling a pad), and |
| does not check in <STRONG>wrefresh</STRONG> to ensure that the pad is refreshed |
| properly. |
| |
| <STRONG>o</STRONG> Solaris <EM>xcurses</EM> checks whether a window is a pad in <STRONG>wnoutrefresh</STRONG>, |
| returning <STRONG>ERR</STRONG> in that case. |
| |
| However, it only sets the flag for subwindows if the parent window |
| is a pad. Its <STRONG>newpad</STRONG> function does not set this information. |
| Consequently, the check will never fail. |
| |
| It makes no comparable check in <STRONG>pnoutrefresh</STRONG>, though interestingly |
| enough, a comment in the source code states that the lack of a |
| check was an MKS extension. |
| |
| <STRONG>o</STRONG> NetBSD 7 <EM>curses</EM> sets a flag in the <EM>WINDOW</EM> structure for <STRONG>newpad</STRONG> and |
| <STRONG>subpad</STRONG>, using this to help with the distinction between |
| <STRONG>wnoutrefresh</STRONG> and <STRONG>pnoutrefresh</STRONG>. |
| |
| It does not check for the case where a subwindow is created in a |
| pad using <STRONG>subwin</STRONG> or <STRONG>derwin</STRONG>. |
| |
| The <STRONG>dupwin</STRONG> function returns a regular window when duplicating a |
| pad. Likewise, <STRONG>getwin</STRONG> always returns a window, even if the saved |
| data was from a pad. |
| |
| This implementation |
| |
| <STRONG>o</STRONG> sets a flag in the <EM>WINDOW</EM> structure for <STRONG>newpad</STRONG> and <STRONG>subpad</STRONG>, |
| |
| <STRONG>o</STRONG> allows a <STRONG>subwin</STRONG> or <STRONG>derwin</STRONG> call to succeed having a pad parent by |
| forcing the subwindow to be a pad, |
| |
| <STRONG>o</STRONG> checks in both <STRONG>wnoutrefresh</STRONG> and <STRONG>pnoutrefresh</STRONG> to ensure that pads |
| and windows are handled distinctly, and |
| |
| <STRONG>o</STRONG> ensures that <STRONG>dupwin</STRONG> and <STRONG>getwin</STRONG> treat pads versus windows |
| consistently. |
| |
| |
| </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE> |
| <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_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG><A HREF="curs_touch.3x.html">curs_touch(3x)</A></STRONG> |
| |
| |
| |
| ncurses 6.5 2024-04-27 <STRONG><A HREF="curs_pad.3x.html">curs_pad(3x)</A></STRONG> |
| </PRE> |
| <div class="nav"> |
| <ul> |
| <li><a href="#h2-NAME">NAME</a></li> |
| <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li> |
| <li><a href="#h2-DESCRIPTION">DESCRIPTION</a> |
| <ul> |
| <li><a href="#h3-newpad">newpad</a></li> |
| <li><a href="#h3-subpad">subpad</a></li> |
| <li><a href="#h3-prefresh_pnoutrefresh">prefresh, pnoutrefresh</a></li> |
| <li><a href="#h3-pechochar">pechochar</a></li> |
| <li><a href="#h3-pecho_wchar">pecho_wchar</a></li> |
| </ul> |
| </li> |
| <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li> |
| <li><a href="#h2-NOTES">NOTES</a></li> |
| <li><a href="#h2-PORTABILITY">PORTABILITY</a></li> |
| <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li> |
| </ul> |
| </div> |
| </BODY> |
| </HTML> |