]> ncurses.scripts.mit.edu Git - ncurses.git/blobdiff - doc/html/man/curs_add_wch.3x.html
ncurses 6.1 - patch 20191026
[ncurses.git] / doc / html / man / curs_add_wch.3x.html
index b33c693e2033b42f4e3644d97046ef105571330f..f7f0c2432e05f27b9401122290a2718e07a58f0a 100644 (file)
@@ -1,6 +1,6 @@
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-  * @Id: curs_add_wch.3x,v 1.17 2017/01/07 19:25:15 tom Exp @
+  * @Id: curs_add_wch.3x,v 1.25 2019/10/27 00:07:13 tom Exp @
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 <TITLE>curs_add_wch 3x</TITLE>
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 <H1 class="no-header">curs_add_wch 3x</H1>
 <PRE>
-<STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>                                       <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
+<STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>                                              <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
 
 
 
 
 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
-       <STRONG>add_wch</STRONG>,   <STRONG>wadd_wch</STRONG>,  <STRONG>mvadd_wch</STRONG>,  <STRONG>mvwadd_wch</STRONG>,  <STRONG>echo_wchar</STRONG>,
-       <STRONG>wecho_wchar</STRONG> - add a complex character and rendition  to  a
-       <STRONG>curses</STRONG> window, then advance the cursor
+       <STRONG>add_wch</STRONG>, <STRONG>wadd_wch</STRONG>, <STRONG>mvadd_wch</STRONG>, <STRONG>mvwadd_wch</STRONG>, <STRONG>echo_wchar</STRONG>, <STRONG>wecho_wchar</STRONG> - add
+       a complex character and rendition to a <STRONG>curses</STRONG> window, then advance  the
+       cursor
 
 
 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
@@ -57,8 +57,7 @@
        <STRONG>int</STRONG> <STRONG>add_wch(</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
        <STRONG>int</STRONG> <STRONG>wadd_wch(</STRONG> <STRONG>WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
        <STRONG>int</STRONG> <STRONG>mvadd_wch(</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
-       <STRONG>int</STRONG>  <STRONG>mvwadd_wch(</STRONG>  <STRONG>WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG>
-       <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
+       <STRONG>int</STRONG> <STRONG>mvwadd_wch(</STRONG> <STRONG>WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
        <STRONG>int</STRONG> <STRONG>echo_wchar(</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
        <STRONG>int</STRONG> <STRONG>wecho_wchar(</STRONG> <STRONG>WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>cchar_t</STRONG> <STRONG>*</STRONG><EM>wch</EM> <STRONG>);</STRONG>
 
 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
 
 </PRE><H3><a name="h3-add_wch">add_wch</a></H3><PRE>
-       The <STRONG>add_wch</STRONG>, <STRONG>wadd_wch</STRONG>, <STRONG>mvadd_wch</STRONG>, and <STRONG>mvwadd_wch</STRONG> functions
-       put the complex character <EM>wch</EM> into the given window at its
-       current position, which is then advanced.  These functions
-       perform  wrapping and special-character processing as fol-
-       lows:
+       The <STRONG>add_wch</STRONG>, <STRONG>wadd_wch</STRONG>, <STRONG>mvadd_wch</STRONG>, and <STRONG>mvwadd_wch</STRONG> functions put the com-
+       plex character <EM>wch</EM> into the given window at its current position, which
+       is then advanced.  These functions perform wrapping and special-charac-
+       ter processing as follows:
 
-       <STRONG>o</STRONG>   If <EM>wch</EM> refers to a spacing character, then any  previ-
-           ous  character  at  that  location  is removed.  A new
-           character specified by <EM>wch</EM> is placed at that  location
-           with  rendition  specified  by  <EM>wch</EM>.   The cursor then
-           advances to the next spacing character on the screen.
+       <STRONG>o</STRONG>   If <EM>wch</EM> refers to a spacing character, then any  previous  character
+           at  that  location is removed.  A new character specified by <EM>wch</EM> is
+           placed at that location with rendition specified by <EM>wch</EM>.  The  cur-
+           sor then advances to the next spacing character on the screen.
 
-       <STRONG>o</STRONG>   If <EM>wch</EM> refers to a non-spacing character, all previous
-           characters  at  that location are preserved.  The non-
-           spacing characters of <EM>wch</EM> are  added  to  the  spacing
-           complex  character, and the rendition specified by <EM>wch</EM>
-           is ignored.
+       <STRONG>o</STRONG>   If  <EM>wch</EM>  refers to a non-spacing character, all previous characters
+           at that location are preserved.  The non-spacing characters of  <EM>wch</EM>
+           are added to the spacing complex character, and the rendition spec-
+           ified by <EM>wch</EM> is ignored.
 
-       <STRONG>o</STRONG>   If the character  part  of  <EM>wch</EM>  is  a  tab,  newline,
-           backspace  or  other  control character, the window is
-           updated and the cursor moves as if <STRONG>addch</STRONG> were called.
+       <STRONG>o</STRONG>   If the character part of <EM>wch</EM> is a tab, newline, backspace or  other
+           control character, the window is updated and the cursor moves as if
+           <STRONG>addch</STRONG> were called.
 
 
 </PRE><H3><a name="h3-echo_wchar">echo_wchar</a></H3><PRE>
-       The <STRONG>echo_wchar</STRONG> function is functionally  equivalent  to  a
-       call  to <STRONG>add_wch</STRONG> followed by a call to <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG>.  Simi-
-       larly, the <STRONG>wecho_wchar</STRONG> is  functionally  equivalent  to  a
-       call  to  <STRONG>wadd_wch</STRONG>  followed  by  a call to <STRONG>wrefresh</STRONG>.  The
-       knowledge that only a single character is being output  is
-       taken  into consideration and, for non-control characters,
-       a considerable performance gain might be seen by using the
-       *<STRONG>echo</STRONG>* functions instead of their equivalents.
+       The <STRONG>echo_wchar</STRONG> function is functionally equivalent to a call to <STRONG>add_wch</STRONG>
+       followed by a call to <STRONG><A HREF="curs_refresh.3x.html">refresh(3x)</A></STRONG>.  Similarly, the <STRONG>wecho_wchar</STRONG> is func-
+       tionally equivalent to a call to <STRONG>wadd_wch</STRONG> followed by a  call  to  <STRONG>wre-</STRONG>
+       <STRONG>fresh</STRONG>.   The  knowledge that only a single character is being output is
+       taken into consideration and, for non-control characters,  a  consider-
+       able  performance  gain  might  be  seen  by using the *<STRONG>echo</STRONG>* functions
+       instead of their equivalents.
 
 
 </PRE><H3><a name="h3-Line-Graphics">Line Graphics</a></H3><PRE>
-       Like  <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>,  <STRONG>addch_wch</STRONG>  accepts symbols which make it
-       simple to draw lines and  other  frequently  used  special
-       characters.   These  symbols  correspond to the same VT100
-       line-drawing set as <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>.
-
-       <EM>Name</EM>              <EM>Unicode</EM>    <EM>Default</EM>   <EM>Description</EM>
-       ----------------------------------------------------------------
-       WACS_BLOCK        0x25ae     #         solid square block
-       WACS_BOARD        0x2592     #         board of squares
-       WACS_BTEE         0x2534     +         bottom tee
-
-       WACS_BULLET       0x00b7     o         bullet
-       WACS_CKBOARD      0x2592     :         checker board (stipple)
-       WACS_DARROW       0x2193     v         arrow pointing down
-       WACS_DEGREE       0x00b0     '         degree symbol
-       WACS_DIAMOND      0x25c6     +         diamond
-       WACS_GEQUAL       0x2265     &gt;         greater-than-or-equal-to
-       WACS_HLINE        0x2500     -         horizontal line
-       WACS_LANTERN      0x2603     #         lantern symbol
-       WACS_LARROW       0x2190     &lt;         arrow pointing left
-       WACS_LEQUAL       0x2264     &lt;         less-than-or-equal-to
-       WACS_LLCORNER     0x2514     +         lower left-hand corner
-       WACS_LRCORNER     0x2518     +         lower right-hand corner
-       WACS_LTEE         0x2524     +         left tee
-       WACS_NEQUAL       0x2260     !         not-equal
-       WACS_PI           0x03c0     *         greek pi
-       WACS_PLMINUS      0x00b1     #         plus/minus
-       WACS_PLUS         0x253c     +         plus
-       WACS_RARROW       0x2192     &gt;         arrow pointing right
-       WACS_RTEE         0x251c     +         right tee
-       WACS_S1           0x23ba     -         scan line 1
-       WACS_S3           0x23bb     -         scan line 3
-       WACS_S7           0x23bc     -         scan line 7
-       WACS_S9           0x23bd     _         scan line 9
-       WACS_STERLING     0x00a3     f         pound-sterling symbol
-       WACS_TTEE         0x252c     +         top tee
-       WACS_UARROW       0x2191     ^         arrow pointing up
-       WACS_ULCORNER     0x250c     +         upper left-hand corner
-       WACS_URCORNER     0x2510     +         upper right-hand corner
-       WACS_VLINE        0x2502     |         vertical line
-
-       The wide-character configuration of ncurses  also  defines
-       symbols for thick- and double-lines:
-
-       <EM>Name</EM>              <EM>Unicode</EM>   <EM>Default</EM>   <EM>Description</EM>
-       ---------------------------------------------------------------------
-       WACS_T_ULCORNER   0x250f    +         thick upper left corner
-       WACS_T_LLCORNER   0x2517    +         thick lower left corner
-       WACS_T_URCORNER   0x2513    +         thick upper right corner
-       WACS_T_LRCORNER   0x251b    +         thick lower right corner
-       WACS_T_LTEE       0x252b    +         thick tee pointing right
-       WACS_T_RTEE       0x2523    +         thick tee pointing left
-       WACS_T_BTEE       0x253b    +         thick tee pointing up
-       WACS_T_TTEE       0x2533    +         thick tee pointing down
-       WACS_T_HLINE      0x2501    -         thick horizontal line
-       WACS_T_VLINE      0x2503    |         thick vertical line
-       WACS_T_PLUS       0x254b    +         thick large plus or crossover
-       WACS_D_ULCORNER   0x2554    +         double upper left corner
-       WACS_D_LLCORNER   0x255a    +         double lower left corner
-       WACS_D_URCORNER   0x2557    +         double upper right corner
-       WACS_D_LRCORNER   0x255d    +         double lower right corner
-       WACS_D_RTEE       0x2563    +         double tee pointing left
-       WACS_D_LTEE       0x2560    +         double tee pointing right
-       WACS_D_BTEE       0x2569    +         double tee pointing up
-       WACS_D_TTEE       0x2566    +         double tee pointing down
-       WACS_D_HLINE      0x2550    -         double horizontal line
-       WACS_D_VLINE      0x2551    |         double vertical line
-       WACS_D_PLUS       0x256c    +         double large plus or crossover
+       Like <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>, <STRONG>addch_wch</STRONG> accepts symbols which make it simple to  draw
+       lines and other frequently used special characters.  These symbols cor-
+       respond to the same VT100 line-drawing set as <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>.
+
+       <STRONG>ACS</STRONG>               <STRONG>Unicode</STRONG>    <STRONG>ASCII</STRONG>     <STRONG>acsc</STRONG>    <STRONG>Glyph</STRONG>
+       <STRONG>Name</STRONG>              <STRONG>Default</STRONG>    <STRONG>Default</STRONG>   <STRONG>char</STRONG>    <STRONG>Name</STRONG>
+       ------------------------------------------------------------------------
+       WACS_BLOCK        0x25ae     #         0       solid square block
+       WACS_BOARD        0x2592     #         h       board of squares
+       WACS_BTEE         0x2534     +         v       bottom tee
+       WACS_BULLET       0x00b7     o         ~       bullet
+       WACS_CKBOARD      0x2592     :         a       checker board (stipple)
+       WACS_DARROW       0x2193     v         .       arrow pointing down
+       WACS_DEGREE       0x00b0     '         f       degree symbol
+       WACS_DIAMOND      0x25c6     +         `       diamond
+
+       WACS_GEQUAL       0x2265     &gt;         &gt;       greater-than-or-equal-to
+       WACS_HLINE        0x2500     -         q       horizontal line
+       WACS_LANTERN      0x2603     #         i       lantern symbol
+       WACS_LARROW       0x2190     &lt;         ,       arrow pointing left
+       WACS_LEQUAL       0x2264     &lt;         y       less-than-or-equal-to
+       WACS_LLCORNER     0x2514     +         m       lower left-hand corner
+       WACS_LRCORNER     0x2518     +         j       lower right-hand corner
+       WACS_LTEE         0x2524     +         t       left tee
+       WACS_NEQUAL       0x2260     !         |       not-equal
+       WACS_PI           0x03c0     *         {       greek pi
+       WACS_PLMINUS      0x00b1     #         g       plus/minus
+       WACS_PLUS         0x253c     +         n       plus
+       WACS_RARROW       0x2192     &gt;         +       arrow pointing right
+       WACS_RTEE         0x251c     +         u       right tee
+       WACS_S1           0x23ba     -         o       scan line 1
+       WACS_S3           0x23bb     -         p       scan line 3
+       WACS_S7           0x23bc     -         r       scan line 7
+       WACS_S9           0x23bd     _         s       scan line 9
+       WACS_STERLING     0x00a3     f         }       pound-sterling symbol
+       WACS_TTEE         0x252c     +         w       top tee
+       WACS_UARROW       0x2191     ^         -       arrow pointing up
+       WACS_ULCORNER     0x250c     +         l       upper left-hand corner
+       WACS_URCORNER     0x2510     +         k       upper right-hand corner
+       WACS_VLINE        0x2502     |         x       vertical line
+
+       The wide-character configuration of ncurses also  defines  symbols  for
+       thick lines (<STRONG>acsc</STRONG> "J" to "V"):
+
+       <STRONG>ACS</STRONG>               <STRONG>Unicode</STRONG>   <STRONG>ASCII</STRONG>     <STRONG>acsc</STRONG>    <STRONG>Glyph</STRONG>
+       <STRONG>Name</STRONG>              <STRONG>Default</STRONG>   <STRONG>Default</STRONG>   <STRONG>char</STRONG>    <STRONG>Name</STRONG>
+       -----------------------------------------------------------------------
+       WACS_T_BTEE       0x253b    +         V       thick tee pointing up
+       WACS_T_HLINE      0x2501    -         Q       thick horizontal line
+       WACS_T_LLCORNER   0x2517    +         M       thick lower left corner
+       WACS_T_LRCORNER   0x251b    +         J       thick lower right corner
+       WACS_T_LTEE       0x252b    +         T       thick tee pointing right
+       WACS_T_PLUS       0x254b    +         N       thick large plus
+       WACS_T_RTEE       0x2523    +         U       thick tee pointing left
+       WACS_T_TTEE       0x2533    +         W       thick tee pointing down
+       WACS_T_ULCORNER   0x250f    +         L       thick upper left corner
+       WACS_T_URCORNER   0x2513    +         K       thick upper right corner
+       WACS_T_VLINE      0x2503    |         X       thick vertical line
+
+       and for double-lines (<STRONG>acsc</STRONG> "A" to "I"):
+
+       <STRONG>ACS</STRONG>               <STRONG>Unicode</STRONG>   <STRONG>ASCII</STRONG>     <STRONG>acsc</STRONG>    <STRONG>Glyph</STRONG>
+       <STRONG>Name</STRONG>              <STRONG>Default</STRONG>   <STRONG>Default</STRONG>   <STRONG>char</STRONG>    <STRONG>Name</STRONG>
+       ------------------------------------------------------------------------
+       WACS_D_BTEE       0x2569    +         H       double tee pointing up
+       WACS_D_HLINE      0x2550    -         R       double horizontal line
+       WACS_D_LLCORNER   0x255a    +         D       double lower left corner
+       WACS_D_LRCORNER   0x255d    +         A       double lower right corner
+       WACS_D_LTEE       0x2560    +         F       double tee pointing right
+       WACS_D_PLUS       0x256c    +         E       double large plus
+       WACS_D_RTEE       0x2563    +         G       double tee pointing left
+       WACS_D_TTEE       0x2566    +         I       double tee pointing down
+       WACS_D_ULCORNER   0x2554    +         C       double upper left corner
+       WACS_D_URCORNER   0x2557    +         B       double upper right corner
+       WACS_D_VLINE      0x2551    |         Y       double vertical line
+
+       Unicode's  descriptions  for  these  characters  differs  slightly from
+       ncurses, by introducing the term "light"  (along  with  less  important
+       details).   Here are its descriptions for the normal, thick, and double
+       horizontal lines:
+
+       <STRONG>o</STRONG>   U+2500 BOX DRAWINGS LIGHT HORIZONTAL
+
+       <STRONG>o</STRONG>   U+2501 BOX DRAWINGS HEAVY HORIZONTAL
+
+       <STRONG>o</STRONG>   U+2550 BOX DRAWINGS DOUBLE HORIZONTAL
 
 
 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
-       All routines return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> on
-       success.
+       All routines return the integer <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> on success.
 
-       Functions with a "mv" prefix first perform a cursor  move-
-       ment  using  <STRONG>wmove</STRONG>, and return an error if the position is
-       outside the window, or if the window pointer is null.
+       Functions with a "mv" prefix first  perform  a  cursor  movement  using
+       <STRONG>wmove</STRONG>, and return an error if the position is outside the window, or if
+       the window pointer is null.
 
 
 </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
-       Note that <STRONG>add_wch</STRONG>, <STRONG>mvadd_wch</STRONG>, <STRONG>mvwadd_wch</STRONG>,  and  <STRONG>echo_wchar</STRONG>
-       may be macros.
+       Note that <STRONG>add_wch</STRONG>, <STRONG>mvadd_wch</STRONG>, <STRONG>mvwadd_wch</STRONG>, and <STRONG>echo_wchar</STRONG> may be macros.
 
 
 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
-       All  of  these  functions  are described in the XSI Curses
-       standard, Issue 4.  The defaults specified for  line-draw-
-       ing characters apply in the POSIX locale.
-
-       X/Open Curses makes it clear that the WACS_ symbols should
-       be defined as a pointer to <STRONG>cchar_t</STRONG> data, e.g., in the dis-
-       cussion of <STRONG>border_set</STRONG>.  A few implementations are problem-
-       atic:
-
-       <STRONG>o</STRONG>   NetBSD curses defines the symbols as a <STRONG>wchar_t</STRONG>  within
-           a <STRONG>cchar_t</STRONG>.
-
-       <STRONG>o</STRONG>   HPUX  curses  equates  some of the <EM>ACS</EM><STRONG>_</STRONG> symbols to the
-           analogous <EM>WACS</EM><STRONG>_</STRONG> symbols as if the  <EM>ACS</EM><STRONG>_</STRONG>  symbols  were
-           wide  characters.   The  misdefined  symbols  are  the
-           arrows and other symbols which are not used for  line-
-           drawing.
-
-       X/Open  Curses  does not define symbols for thick- or dou-
-       ble-lines.   SVr4  curses  implementations  defined  their
-       line-drawing  symbols  in  terms  of intermediate symbols.
-       This implementation extends those symbols,  providing  new
-       definitions which are not in the SVr4 implementations.
+       All of these functions are described in the XSI Curses standard,  Issue
+       4.   The  defaults  specified  for line-drawing characters apply in the
+       POSIX locale.
+
+       X/Open Curses makes it clear that the WACS_ symbols should  be  defined
+       as a pointer to <STRONG>cchar_t</STRONG> data, e.g., in the discussion of <STRONG>border_set</STRONG>.  A
+       few implementations are problematic:
+
+       <STRONG>o</STRONG>   NetBSD curses defines the symbols as a <STRONG>wchar_t</STRONG> within a <STRONG>cchar_t</STRONG>.
+
+       <STRONG>o</STRONG>   HPUX curses equates some of the <EM>ACS</EM><STRONG>_</STRONG> symbols to the analogous <EM>WACS</EM><STRONG>_</STRONG>
+           symbols  as  if  the <EM>ACS</EM><STRONG>_</STRONG> symbols were wide characters.  The misde-
+           fined symbols are the arrows and other symbols which are  not  used
+           for line-drawing.
+
+       X/Open Curses does not define symbols for thick- or double-lines.  SVr4
+       curses implementations defined their line-drawing symbols in  terms  of
+       intermediate  symbols.  This implementation extends those symbols, pro-
+       viding new definitions which are not in the SVr4 implementations.
+
+       Not all  Unicode-capable  terminals  provide  support  for  VT100-style
+       alternate character sets (i.e., the <STRONG>acsc</STRONG> capability), with their corre-
+       sponding line-drawing characters.  X/Open Curses did  not  address  the
+       aspect  of  integrating Unicode with line-drawing characters.  Existing
+       implementations of Unix curses (AIX, HPUX, Solaris) use only  the  <STRONG>acsc</STRONG>
+       character-mapping  to  provide this feature.  As a result, those imple-
+       mentations can only use single-byte line-drawing  characters.   Ncurses
+       5.3  (2002) provided a table of Unicode values to solve these problems.
+       NetBSD curses incorporated that table in 2010.
+
+       In this implementation, the Unicode values are used instead of the ter-
+       minal  description's  <STRONG>acsc</STRONG>  mapping as discussed in <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG> for the
+       environment variable <STRONG>NCURSES_NO_UTF8_ACS</STRONG>.  In contrast,  for  the  same
+       cases, the line-drawing characters described in <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG> will use
+       only the ASCII default values.
+
+       Having Unicode available does not solve all of the problems with  line-
+       drawing for curses:
+
+       <STRONG>o</STRONG>   The  closest  Unicode  equivalents to the VT100 graphics <EM>S1</EM>, <EM>S3</EM>, <EM>S7</EM>
+           and <EM>S9</EM> frequently are not displayed at the regular intervals  which
+           the terminal used.
+
+       <STRONG>o</STRONG>   The  <EM>lantern</EM>  is  a special case.  It originated with the AT&amp;T 4410
+           terminal in the early 1980s.  There is no accessible  documentation
+           depicting the lantern symbol on the AT&amp;T terminal.
+
+           Lacking documentation, most readers assume that a <EM>storm</EM> <EM>lantern</EM> was
+           intended.  But there are several possibilities, all with problems.
+
+           Unicode 6.0 (2010) does provide two lantern  symbols:  U+1F383  and
+           U+1F3EE.   Those  were  not  available  in 2002, and are irrelevant
+           since they lie outside the BMP and as a result  are  not  generally
+           available in terminals.  They are not storm lanterns, in any case.
+
+           Most <EM>storm</EM> <EM>lanterns</EM> have a tapering glass chimney (to guard against
+           tipping); some have a wire grid protecting the chimney.
+
+           For the tapering appearance,  U+2603 was adequate.   In  use  on  a
+           terminal, no one can tell what the image represents.  Unicode calls
+           it a snowman.
+
+           Others have suggested these alternatives: S U+00A7 (section  mark),
+           <STRONG>O</STRONG> U+0398 (theta), <STRONG>O</STRONG> U+03A6 (phi), d U+03B4 (delta),  U+2327 (x in a
+           rectangle),  U+256C (forms double  vertical  and  horizontal),  and
+           U+2612 (ballot box with x).
 
 
 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
-       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>,
-       <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG>putwc(3)</STRONG>
+       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>, <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>, <STRONG><A HREF="curs_clear.3x.html">curs_clear(3x)</A></STRONG>, <STRONG>curs_out-</STRONG>
+       <STRONG><A HREF="curs_outopts.3x.html">opts(3x)</A></STRONG>, <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>, <STRONG>putwc(3)</STRONG>
 
 
 
-                                                       <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
+                                                              <STRONG><A HREF="curs_add_wch.3x.html">curs_add_wch(3x)</A></STRONG>
 </PRE>
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