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<H1 class="no-header">curs_inch 3x 2025-02-15 ncurses 6.6 Library calls</H1>
<PRE>
<STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>                    Library calls                   <STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>


</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>inch</STRONG>, <STRONG>winch</STRONG>, <STRONG>mvinch</STRONG>, <STRONG>mvwinch</STRONG> - get a <EM>curses</EM> character from a window


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

       <STRONG>chtype</STRONG> <STRONG>inch(void);</STRONG>
       <STRONG>chtype</STRONG> <STRONG>winch(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>);</STRONG>
       <STRONG>chtype</STRONG> <STRONG>mvinch(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>);</STRONG>
       <STRONG>chtype</STRONG> <STRONG>mvwinch(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>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       <STRONG>winch</STRONG>  returns the <EM>curses</EM> character, including its attributes and color
       pair identifier, at the cursor position in the window <EM>win</EM>.   Subsection
       "Video  Attributes"  of  <STRONG><A HREF="curs_attr.3x.html">attron(3x)</A></STRONG>  explains how to extract these data
       from a <EM>chtype</EM>.  <STRONG><A HREF="ncurses.3x.html">ncurses(3x)</A></STRONG> describes the variants of this function.


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       These functions return <STRONG>OK</STRONG> on success and <STRONG>ERR</STRONG> on failure.

       In <EM>ncurses</EM>, they return <STRONG>ERR</STRONG> if <EM>win</EM> is <EM>NULL</EM>.

       Functions prefixed with "mv" first perform cursor movement and fail  if
       the position (<EM>y</EM>, <EM>x</EM>) is outside the window boundaries.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       <STRONG>inch</STRONG>, <STRONG>mvinch</STRONG>, and <STRONG>mvwinch</STRONG> may be implemented as macros.

       These  functions  do  not  fail  if the window contains cells of <EM>curses</EM>
       complex characters; that is, if  they  contain  characters  with  codes
       wider  than  eight  bits  (or  greater  than 255 as an unsigned decimal
       integer).  They instead extract only the low-order eight  bits  of  the
       character code from the cell.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       X/Open Curses Issue 4 describes these functions.  It specifies no error
       conditions for them.


</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
       The  original  <EM>curses</EM> in 4BSD (1980) defined <EM>winch</EM> as a macro accessing
       the <EM>WINDOW</EM> structure member representing character cell data,  at  that
       time  a  <EM>char</EM>,  containing  only  a  7-bit  ASCII  character code and a
       "standout" attribute bit, the only one the library supported.

       SVr2 <EM>curses</EM> (1984) extended this approach, widening the character  code
       to  eight bits and permitting several attributes to be combined with it
       by storing them together in a  <EM>chtype</EM>,  an  alias  of  <EM>unsigned</EM>  <EM>short</EM>.
       Because  a macro was used, its value was not type-checked as a function
       return value could have been.  Goodheart documented SVr3  (1987)  <EM>winch</EM>
       as  returning  an  <EM>int</EM>.   SVr3.1's  (1987)  <EM>chtype</EM>  became  an alias of
       <EM>unsigned</EM> <EM>long</EM>, using 16 bits for the character code  and  widening  the
       type in practical terms to 32 bits, as 64-bit Unix systems were not yet
       in wide use, and fixed-width integral types would not be standard until
       ISO  C99.   SVr3.2 (1988) added a 6-bit color pair identifier alongside
       the attributes.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="curs_in_wch.3x.html">curs_in_wch(3x)</A></STRONG> describes comparable functions of the  <EM>ncurses</EM>  library
       in its wide-character configuration (<EM>ncursesw</EM>).

       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_instr.3x.html">curs_instr(3x)</A></STRONG>

ncurses 6.6                       2025-02-15                     <STRONG><A HREF="curs_inch.3x.html">curs_inch(3x)</A></STRONG>
</PRE>
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<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-HISTORY">HISTORY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
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