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+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)intro.5	8.1 (Berkeley) 6/4/93
+.\"
+.sh 1 "Character Output and Scrolling"
+.pp
+The character output policy deals with the following problems.  First,
+where is the location of the cursor after a character is printed, and 
+secondly, when does the screen scroll if scrolling is enabled.
+.pp
+In the normal case the characters are output as expected, with the cursor 
+occupying the position of the next character to be output.  However, when the
+cursor is on the last column of the line, the cursor will remain on that 
+position after the last character on the line is output and will only assume
+the position on the next line when the next character (the first on the next
+line) is output.
+.pp
+Likewise, if scrolling is enabled, a scroll will be invoked only when the
+first character on he first line past the bottom line of the window is
+output.  If scrolling is not enabled the chracters will to be output to the
+bottom right corner of the window which is the cursor location.
+.pp
+This policy allows consistent behavior of the cursor at the boundary 
+conditions.  Furthermore, it prevents a scroll from happening before it is
+actually needed (the old package used to scroll when the bottom right position
+was output a character).  As a precendent, it models the 
+.i xterm
+character output conventions.
+.sh 1 "Terminal State Handling"
+.pp
+The variable
+.Vn curses_termios
+contains the terminal state of the terminal.  Certain historical routines 
+return information:
+.Fn baudrate , 
+.Fn erasechar ,
+.Fn killchar ,
+and 
+.Fn ospeed .
+These routines are obsolete and exist only for backward compatibility.  If
+you wish to use the information in the 
+.Vn curses_termios
+structure, you should use the
+\fItsetattr\fP(3) 
+routines.
+.sh 1 "Subwindows"
+.pp
+Subwindows are windows which do not have an independent text structure, 
+.i i.e. , 
+they are windows whose text is a subset of the text of a larger window: the
+.i parent 
+window.  One consequence of this is that changes to either the parent or the
+child window are destructive to the other, 
+.i i.e. , 
+a change to the subwindow is also a change to the parent window and a change 
+to the parent window in the region defined by the subwindow is implicitly a 
+change to the subwindow as well.
+Apart from this detail, subwindows function like any other window.