* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************
- * @Id: curs_initscr.3x,v 1.37 2022/02/12 20:07:29 tom Exp @
+ * @Id: curs_initscr.3x,v 1.39 2022/07/24 15:46:49 tom Exp @
-->
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<STRONG>o</STRONG> This implementation allows using <STRONG>initscr</STRONG> after <STRONG>endwin</STRONG>.
- Old versions of curses, e.g., BSD 4.4, may have returned a null pointer
- from <STRONG>initscr</STRONG> when an error is detected, rather than exiting. It is
- safe but redundant to check the return value of <STRONG>initscr</STRONG> in XSI Curses.
+ Old versions of curses, e.g., BSD 4.4, would return a null pointer from
+ <STRONG>initscr</STRONG> when an error is detected, rather than exiting. It is safe but
+ redundant to check the return value of <STRONG>initscr</STRONG> in XSI Curses.
+
+ Calling <STRONG>endwin</STRONG> does not dispose of the memory allocated in <STRONG>initscr</STRONG> or
+ <STRONG>newterm</STRONG>. Deleting a <STRONG>SCREEN</STRONG> provides a way to do this:
+
+ <STRONG>o</STRONG> X/Open Curses does not say what happens to <STRONG>WINDOW</STRONG>s when <STRONG>delscreen</STRONG>
+ "frees storage associated with the <STRONG>SCREEN</STRONG>" nor does the SVr4 docu-
+ mentation help, adding that it should be called after <STRONG>endwin</STRONG> if a
+ <STRONG>SCREEN</STRONG> is no longer needed.
+
+ <STRONG>o</STRONG> However, <STRONG>WINDOW</STRONG>s are implicitly associated with a <STRONG>SCREEN</STRONG>. so that
+ it is reasonable to expect <STRONG>delscreen</STRONG> to deal with these.
+
+ <STRONG>o</STRONG> SVr4 curses deletes the standard <STRONG>WINDOW</STRONG> structures <STRONG>stdscr</STRONG> and
+ <STRONG>curscr</STRONG> as well as a work area <STRONG>newscr</STRONG>. SVr4 curses ignores other
+ windows.
+
+ <STRONG>o</STRONG> Since version 4.0 (1996), ncurses has maintained a list of all win-
+ dows for each screen, using that information to delete those win-
+ dows when <STRONG>delscreen</STRONG> is called.
+
+ <STRONG>o</STRONG> NetBSD copied this feature of ncurses in 2001. PDCurses follows
+ the SVr4 model, deleting only the standard <STRONG>WINDOW</STRONG> structures.
</PRE><H3><a name="h3-Unset-TERM-Variable">Unset TERM Variable</a></H3><PRE>
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