+ This setting is obsolete. Before changes
+
+ <STRONG>o</STRONG> started with 5.9 patch 20120825 and
+
+ <STRONG>o</STRONG> continued though 5.9 patch 20130126
+
+ <STRONG>ncurses</STRONG> enabled buffered output during terminal ini-
+ tialization. This was done (as in SVr4 curses) for
+ performance reasons. For testing purposes, both of
+ <STRONG>ncurses</STRONG> and certain applications, this feature was
+ made optional. Setting the NCURSES_NO_SETBUF vari-
+ able disabled output buffering, leaving the output in
+ the original (usually line buffered) mode.
+
+ In the current implementation, ncurses performs its
+ own buffering and does not require this workaround.
+ It does not modify the buffering of the standard out-
+ put.
+
+ The reason for the change was to make the behavior
+ for interrupts and other signals more robust. One
+ drawback is that certain nonconventional programs
+ would mix ordinary stdio calls with ncurses calls and
+ (usually) work. This is no longer possible since
+ ncurses is not using the buffered standard output but
+ its own output (to the same file descriptor). As a
+ special case, the low-level calls such as <STRONG>putp</STRONG> still
+ use the standard output. But high-level curses calls
+ do not.
+
+ NCURSES_NO_UTF8_ACS
+ During initialization, the <STRONG>ncurses</STRONG> library checks for
+ special cases where VT100 line-drawing (and the cor-
+ responding alternate character set capabilities)
+ described in the terminfo are known to be missing.
+ Specifically, when running in a UTF-8 locale, the
+ Linux console emulator and the GNU screen program
+ ignore these. Ncurses checks the TERM environment
+ variable for these. For other special cases, you
+ should set this environment variable. Doing this
+ tells ncurses to use Unicode values which correspond
+ to the VT100 line-drawing glyphs. That works for the
+ special cases cited, and is likely to work for termi-
+ nal emulators.
+
+ When setting this variable, you should set it to a
+ nonzero value. Setting it to zero (or to a nonnum-
+ ber) disables the special check for "linux" and
+ "screen".
+
+ As an alternative to the environment variable,
+ ncurses checks for an extended terminfo capability
+ <STRONG>U8</STRONG>. This is a numeric capability which can be com-
+ piled using <STRONG>tic</STRONG> <STRONG>-x</STRONG>. For example
+
+ # linux console, if patched to provide working
+ # VT100 shift-in/shift-out, with corresponding font.
+ linux-vt100|linux console with VT100 line-graphics,
+ U8#0, use=linux,
+
+ # uxterm with vt100Graphics resource set to false
+ xterm-utf8|xterm relying on UTF-8 line-graphics,
+ U8#1, use=xterm,
+
+ The name "U8" is chosen to be two characters, to per-
+ mit it to be used by applications that use ncurses'
+ termcap interface.