+'\" t
.\"***************************************************************************
.\" Copyright (c) 1998-2011,2012 Free Software Foundation, Inc. *
.\" *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: curs_util.3x,v 1.35 2012/07/15 00:23:52 tom Exp $
+.\" $Id: curs_util.3x,v 1.36 2012/07/21 18:51:10 tom Exp $
.TH curs_util 3X ""
.de bP
.IP \(bu 4
Normally ncurses looks first at the terminal database for the screen size.
.IP
If \fBuse_env\fP was called with \fBFALSE\fP for parameter,
-it stops here.
+it stops here unless
+If \fBuse_tioctl\fP was also called with \fBTRUE\fP for parameter.
.bP
Then it asks for the screen size via operating system calls.
If successful,
it overrides the values from the terminal database.
.bP
-Finally, ncurses examines the
-\fBLINES\fR or \fBCOLUMNS\fR environment variables,
+Finally (unless \fBuse_env\fP was called with \fBFALSE\fP parameter),
+ncurses examines the \fBLINES\fR or \fBCOLUMNS\fR environment variables,
using a value in those to override the results
from the operating system or terminal database.
.IP
ncurses re-fetches the value of the environment variables so that
it is still the environment variables which set the screen size.
.PP
+The \fBuse_env\fP and \fBuse_tioctl\fP routines combine as
+summarized here:
+.TS
+center tab(/);
+l l l
+_ _ _
+lw7 lw7 lw40.
+\fIuse_env\fR/\fIuse_tioctl\fR/\fISummary\fR
+TRUE/FALSE/T{
+This is the default behavior.
+ncurses uses operating system calls
+unless overridden by $LINES or $COLUMNS environment variables.
+T}
+TRUE/TRUE/T{
+ncurses updates $LINES and $COLUMNS based on operating system calls.
+T}
+FALSE/TRUE/T{
+ncurses ignores $LINES and $COLUMNS, uses operating system calls to obtain size.
+T}
+FALSE/FALSE/T{
+ncurses relies on the terminal database to determine size.
+T}
+.TE
+.PP
The \fBputwin\fR routine writes all data associated with window \fIwin\fR into
the file to which \fIfilep\fR points. This information can be later retrieved
using the \fBgetwin\fR function.