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ncurses 6.5 - patch 20240601
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diff --git a/doc/html/man/curs_scr_dump.3x.html b/doc/html/man/curs_scr_dump.3x.html
index 3a6332d2d6eedb408908730a6718b1e4f506f170..052af277f52890490381206588bd22fc965e8cd2 100644 (file)
--- a/doc/html/man/curs_scr_dump.3x.html
+++ b/doc/html/man/curs_scr_dump.3x.html
@@ -1,6 +1,6 @@
 <!--
   ****************************************************************************
 <!--
   ****************************************************************************
-  * Copyright 2018-2021,2022 Thomas E. Dickey                                *
+  * Copyright 2018-2023,2024 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  *
@@ -27,19 +27,19 @@
   * sale, use or other dealings in this Software without prior written       *
   * authorization.                                                           *
   ****************************************************************************
   * sale, use or other dealings in this Software without prior written       *
   * authorization.                                                           *
   ****************************************************************************
-  * @Id: curs_scr_dump.3x,v 1.21 2022/02/12 20:05:11 tom Exp @
+  * @Id: curs_scr_dump.3x,v 1.45 2024/06/01 22:29:45 tom Exp @
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-<TITLE>curs_scr_dump 3x 2022-02-12 ncurses 6.4 Library calls</TITLE>
+<TITLE>curs_scr_dump 3x 2024-06-01 ncurses 6.5 Library calls</TITLE>
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-<H1 class="no-header">curs_scr_dump 3x 2022-02-12 ncurses 6.4 Library calls</H1>
+<H1 class="no-header">curs_scr_dump 3x 2024-06-01 ncurses 6.5 Library calls</H1>
 <PRE>
 <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>                Library calls               <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>
 
 <PRE>
 <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>                Library calls               <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>
 
@@ -47,86 +47,111 @@
 
 
 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
 
 
 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
-       <STRONG>scr_dump</STRONG>, <STRONG>scr_restore</STRONG>, <STRONG>scr_init</STRONG>, <STRONG>scr_set</STRONG> - read (write) a <STRONG>curses</STRONG> screen
-       from (to) a file
+       <STRONG>scr_dump</STRONG>,  <STRONG>scr_restore</STRONG>,  <STRONG>scr_init</STRONG>, <STRONG>scr_set</STRONG> - read/write a <EM>curses</EM> screen
+       from/to a file
 
 
 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
        <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
 
 
 
 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
        <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
 
-       <STRONG>int</STRONG> <STRONG>scr_dump(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>filename</EM><STRONG>);</STRONG>
-       <STRONG>int</STRONG> <STRONG>scr_restore(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>filename</EM><STRONG>);</STRONG>
-       <STRONG>int</STRONG> <STRONG>scr_init(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>filename</EM><STRONG>);</STRONG>
-       <STRONG>int</STRONG> <STRONG>scr_set(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG><EM>filename</EM><STRONG>);</STRONG>
+       <STRONG>int</STRONG> <STRONG>scr_dump(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>filename</EM><STRONG>);</STRONG>
+       <STRONG>int</STRONG> <STRONG>scr_restore(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>filename</EM><STRONG>);</STRONG>
+       <STRONG>int</STRONG> <STRONG>scr_init(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>filename</EM><STRONG>);</STRONG>
+       <STRONG>int</STRONG> <STRONG>scr_set(const</STRONG> <STRONG>char</STRONG> <STRONG>*</STRONG> <EM>filename</EM><STRONG>);</STRONG>
 
 
 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
 
 
 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
+       <EM>curses</EM> provides applications the ability to write the contents  of  the
+       screen  to  a  file and read them back.  To read/write a window (rather
+       than the whole screen) from/to a file, use <STRONG><A HREF="curs_util.3x.html">getwin(3x)</A></STRONG>  and  <STRONG><A HREF="curs_util.3x.html">putwin(3x)</A></STRONG>,
+       respectively.
+
 
 </PRE><H3><a name="h3-scr_dump">scr_dump</a></H3><PRE>
 
 </PRE><H3><a name="h3-scr_dump">scr_dump</a></H3><PRE>
-       The <STRONG>scr_dump</STRONG> routine dumps the current contents of the  <EM>virtual</EM>  <EM>screen</EM>
-       to the file <EM>filename</EM>.
+       <STRONG>scr_dump</STRONG>  writes  to  <EM>filename</EM>  the contents of the virtual screen; see
+       <STRONG><A HREF="curs_variables.3x.html">curscr(3x)</A></STRONG>.
 
 
 </PRE><H3><a name="h3-scr_restore">scr_restore</a></H3><PRE>
 
 
 </PRE><H3><a name="h3-scr_restore">scr_restore</a></H3><PRE>
-       The  <STRONG>scr_restore</STRONG>  routine  sets  the  <EM>virtual</EM> <EM>screen</EM> to the contents of
-       <EM>filename</EM>, which must have been written using <STRONG>scr_dump</STRONG>.  The  next  call
-       to  <STRONG>doupdate</STRONG>  restores  the <EM>physical</EM> <EM>screen</EM> to the way it looked in the
-       dump file.
+       <STRONG>scr_restore</STRONG> updates  the  virtual  screen  to  match  the  contents  of
+       <EM>filename</EM> (if validly written with <STRONG>scr_dump</STRONG>).  <EM>curses</EM> does not perform a
+       refresh;  after  making  any  desired  changes,  call  <STRONG><A HREF="curs_refresh.3x.html">doupdate(3x)</A></STRONG>  or
+       similar.
 
 
 </PRE><H3><a name="h3-scr_init">scr_init</a></H3><PRE>
 
 
 </PRE><H3><a name="h3-scr_init">scr_init</a></H3><PRE>
-       The <STRONG>scr_init</STRONG> routine reads in the contents of <EM>filename</EM> and uses them to
-       initialize the <STRONG>curses</STRONG> data structures about what the terminal currently
-       has on its screen.  If the data is determined to be valid, <STRONG>curses</STRONG> bases
-       its  next update of the screen on this information rather than clearing
-       the  screen  and  starting  from  scratch.   <STRONG>scr_init</STRONG>  is  used   after
-       <STRONG><A HREF="curs_initscr.3x.html">initscr(3x)</A></STRONG>  or  a  <STRONG>system(3)</STRONG>  call  to  share  the screen with another
-       process which has done a <STRONG>scr_dump</STRONG> after its <STRONG><A HREF="curs_initscr.3x.html">endwin(3x)</A></STRONG> call.  The  data
-       is declared invalid
+       <STRONG>scr_init</STRONG>  reads <EM>filename</EM>, using it to initialize <EM>curses</EM> data structures
+       describing the state of  the  terminal  screen.   <EM>curses</EM>  then,  if  it
+       decides  the  terminal  state  is  valid,  bases its next update of the
+       screen on this information rather than clearing it  and  starting  from
+       scratch.
 
 
-       <STRONG>o</STRONG>   if the terminfo capabilities <STRONG>rmcup</STRONG> and <STRONG>nrrmc</STRONG> exist, also
+       <EM>curses</EM>  regards  the terminal being in an invalid state for computation
+       of updates based on the contents of <EM>filename</EM> if
 
 
-       <STRONG>o</STRONG>   if  the  terminal  has been written to since the preceding <STRONG>scr_dump</STRONG>
-           call.
+       <STRONG>o</STRONG>   the terminal type supports the <EM>terminfo</EM>  capabilities  <STRONG>exit_ca_mode</STRONG>
+           (<STRONG>rmcup</STRONG>) or <STRONG>non_rev_rmcup</STRONG> (<STRONG>nrrmc</STRONG>), or
 
 
+       <STRONG>o</STRONG>   <EM>curses</EM>  knows  that  the  terminal  has  been  written to since the
+           preceding <STRONG>scr_dump</STRONG> call.
+
+       Either of the foregoing conditions means that <EM>curses</EM> cannot assume that
+       the  terminal's  contents  match their representation in <EM>filename</EM>.  The
+       former is due to  terminal  features  (such  as  <STRONG>xterm(1)</STRONG>'s  "alternate
+       screen")  that  couple  cursor-positioning  mode  with a local cache of
+       screen contents.  <EM>curses</EM> cannot know  whether  terminal  is  displaying
+       from that local cache at the time the application calls <STRONG>scr_init</STRONG>, so it
+       makes a pessimistic assumption that a  full  redraw  is  required;  see
+       subsection "Cursor Motions" of <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.
+
+       <STRONG>scr_init</STRONG>  could  be  used  after  <STRONG><A HREF="curs_initscr.3x.html">initscr(3x)</A></STRONG> or <STRONG>system(3)</STRONG> to share the
+       screen with another process that has done a <STRONG>scr_dump</STRONG> after  <STRONG><A HREF="curs_initscr.3x.html">endwin(3x)</A></STRONG>.
+       An   application  that  supports  suspending  its  state  on  exit  and
+       subsequent resumption upon  later  execution  might  use  <STRONG>scr_dump</STRONG>  and
+       <STRONG>scr_init</STRONG> thus.
 
 
-</PRE><H3><a name="h3-scr_set">scr_set</a></H3><PRE>
-       The <STRONG>scr_set</STRONG> routine is a combination of <STRONG>scr_restore</STRONG> and  <STRONG>scr_init</STRONG>.   It
-       tells the program that the information in <EM>filename</EM> is what is currently
-       on the screen, and also what the program wants on the screen.  This can
-       be thought of as a screen inheritance function.
 
 
-       To  read  (write)  a window from (to) a file, use the <STRONG>getwin</STRONG> and <STRONG>putwin</STRONG>
-       routines [see <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>].
+</PRE><H3><a name="h3-scr_set">scr_set</a></H3><PRE>
+       <STRONG>scr_set</STRONG>  combines  <STRONG>scr_restore</STRONG> and <STRONG>scr_init</STRONG>, synchronizing the contents
+       of <EM>filename</EM> with the virtual screen.  It can be regarded  as  a  screen
+       inheritance function; consider a real-time screen-sharing application.
 
 
 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
 
 
 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
-       All routines return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> upon success.
+       These functions return <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure.
 
 
-       X/Open defines no error conditions.  In this implementation, each  will
-       return an error if the file cannot be opened.
+       In  <EM>ncurses</EM>,  each  function  returns  <STRONG>ERR</STRONG>  if it cannot open <EM>filename</EM>.
+       <STRONG>scr_init</STRONG>, <STRONG>scr_restore</STRONG>, and  <STRONG>scr_set</STRONG>  return  <STRONG>ERR</STRONG>  if  the  contents  of
+       <EM>filename</EM> are invalid.
 
 
 </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
 
 
 </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
-       Note that <STRONG>scr_init</STRONG>, <STRONG>scr_set</STRONG>, and <STRONG>scr_restore</STRONG> may be macros.
+       <STRONG>scr_init</STRONG>, <STRONG>scr_restore</STRONG>, and <STRONG>scr_set</STRONG> may be implemented as macros.
 
 
 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
 
 
 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
-       The XSI Curses standard, Issue 4, describes these functions (adding the
-       const qualifiers).
+       X/Open  Curses,  Issue  4  describes  these functions.  It specifies no
+       error conditions for them.
+
+       SVr4 omitted the <EM>const</EM> qualifiers.
+
+       SVr4 documentation describes <STRONG>scr_init</STRONG> such that the dump data  is  also
+       considered  invalid  "if the time-stamp of the tty is old" but does not
+       define "old".
+
 
 
-       The SVr4 docs merely say under <STRONG>scr_init</STRONG> that the dump data is also con-
-       sidered invalid "if the time-stamp of the tty is old" but do not define
-       "old".
+</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
+       SVr3 (1987) introduced <STRONG>scr_dump</STRONG>,  <STRONG>scr_init</STRONG>,  and  <STRONG>scr_restore</STRONG>.   SVr3.1
+       added <STRONG>scr_set</STRONG>.
 
 
 </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_initscr.3x.html">curs_initscr(3x)</A></STRONG>,    <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>,    <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>,
 
 
 </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_initscr.3x.html">curs_initscr(3x)</A></STRONG>,    <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>,    <STRONG><A HREF="curs_util.3x.html">curs_util(3x)</A></STRONG>,
-       <STRONG><A HREF="scr_dump.5.html">scr_dump(5)</A></STRONG>, <STRONG>system(3)</STRONG>
+       <STRONG>system(3)</STRONG>, <STRONG><A HREF="scr_dump.5.html">scr_dump(5)</A></STRONG>, <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>
 
 
 
 
 
 
-ncurses 6.4                       2022-02-12                 <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>
+ncurses 6.5                       2024-06-01                 <STRONG><A HREF="curs_scr_dump.3x.html">curs_scr_dump(3x)</A></STRONG>
 </PRE>
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@@ -143,6 +168,7 @@ ncurses 6.4                       2022-02-12                 <STRONG><A HREF="cu
 <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-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-HISTORY">HISTORY</a></li>
 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
 </ul>
 </div>
 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
 </ul>
 </div>
ncurses, with patches starting at ncurses-5.6; new users should use https://github.com/ThomasDickey/ncurses-snapshots/