-As of 4.4BSD, executing \fBtset\fR as \fBreset\fR no longer implies the \fB-Q\fR
-option. Also, the interaction between the - option and the \fIterminal\fR
-argument in some historic implementations of \fBtset\fR has been removed.
+As of 4.4BSD,
+executing \fB@TSET@\fR as \fB@RESET@\fR no longer implies the \fB\-Q\fR option.
+Also, the interaction between the \- option and the \fIterminal\fR
+argument in some historic implementations of \fB@TSET@\fR has been removed.
+.PP
+The \fB\-c\fP and \fB\-w\fP options are not found in earlier implementations.
+However, a different window size-change feature was provided in 4.4BSD.
+.bP
+In 4.4BSD, \fBtset\fP uses the window size from the termcap description
+to set the window size if \fBtset\fP is not able to obtain the window
+size from the operating system.
+.bP
+In ncurses, \fB@TSET@\fR obtains the window size using
+\fBsetupterm\fP, which may be from
+the operating system,
+the \fBLINES\fP and \fBCOLUMNS\fP environment variables or
+the terminal description.
+.PP
+Obtaining the window size from the terminal description is common to
+both implementations, but considered obsolescent.
+Its only practical use is for hardware terminals.
+Generally speaking, a window size would be unset only if there were
+some problem obtaining the value from the operating system
+(and \fBsetupterm\fP would still fail).
+For that reason, the \fBLINES\fP and \fBCOLUMNS\fP environment variables
+may be useful for working around window-size problems.
+Those have the drawback that if the window is resized,
+those variables must be recomputed and reassigned.
+To do this more easily, use the \fBresize\fP(1) program.