ncurses 6.3 - patch 20220724

[ncurses.git] / man / curs_initscr.3x

diff --git a/man/curs_initscr.3x b/man/curs_initscr.3x
index 17e5fb9c5adcd4c39bb45df617e54fd660a5628f..5e17ead0a659bd23838095397ea0e3b03bb0a443 100644 (file)
--- a/man/curs_initscr.3x
+++ b/man/curs_initscr.3x
@@ -27,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" 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 $

 .TH curs_initscr 3X ""
 .de bP
 .ie n  .IP \(bu 4
 .TH curs_initscr 3X ""
 .de bP
 .ie n  .IP \(bu 4


@@ -176,10 +176,35 @@ to restore the screen after \fBendwin\fP.
 .bP
 This implementation allows using \fBinitscr\fP after \fBendwin\fP.
 .PP
 .bP
 This implementation allows using \fBinitscr\fP after \fBendwin\fP.
 .PP

-Old versions of curses, e.g., BSD 4.4, may have returned a null pointer
+Old versions of curses, e.g., BSD 4.4, would return a null pointer

 from \fBinitscr\fP when an error is detected, rather than exiting.
 It is safe but redundant to check the return value of \fBinitscr\fP
 in XSI Curses.
 from \fBinitscr\fP when an error is detected, rather than exiting.
 It is safe but redundant to check the return value of \fBinitscr\fP
 in XSI Curses.

+.PP
+Calling \fBendwin\fP does not dispose of the memory allocated in \fBinitscr\fP
+or \fBnewterm\fP.
+Deleting a \fBSCREEN\fP provides a way to do this:
+.bP
+X/Open Curses does not say what happens to \fBWINDOW\fPs when \fBdelscreen\fP
+\*(``frees storage associated with the \fBSCREEN\fP\*(''
+nor does the SVr4 documentation help,
+adding that it should be called after \fBendwin\fP if a \fBSCREEN\fP
+is no longer needed.
+.bP
+However, \fBWINDOW\fPs are implicitly associated with a \fBSCREEN\fP.
+so that it is reasonable to expect \fBdelscreen\fP to deal with these.
+.bP
+SVr4 curses deletes the standard \fBWINDOW\fP structures
+\fBstdscr\fP and \fBcurscr\fP as well as a work area \fBnewscr\fP.
+SVr4 curses ignores other windows.
+.bP
+Since version 4.0 (1996), ncurses has maintained a list of all windows
+for each screen,
+using that information to delete those windows when \fBdelscreen\fP is called.
+.bP
+NetBSD copied this feature of ncurses in 2001.
+PDCurses follows the SVr4 model,
+deleting only the standard \fBWINDOW\fP structures.

 .SS Unset TERM Variable
 .PP
 If the TERM variable is missing or empty, \fBinitscr\fP uses the
 .SS Unset TERM Variable
 .PP
 If the TERM variable is missing or empty, \fBinitscr\fP uses the