ncurses 4.2
[ncurses.git] / Ada95 / html / curs_clear.3x.html
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3 <PRE>
4        <STRONG>erase</STRONG>,  <STRONG>werase</STRONG>,  <STRONG>clear</STRONG>,  <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, <STRONG>wclrtobot</STRONG>, <STRONG>clr-</STRONG>
5        <STRONG>toeol</STRONG>, <STRONG>wclrtoeol</STRONG> - clear all or part of a <STRONG>curses</STRONG> window
6
7
8 </PRE>
9 <H2>SYNOPSIS</H2><PRE>
10        <STRONG>#</STRONG> <STRONG>include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
11
12        <STRONG>int</STRONG> <STRONG>erase(void);</STRONG>
13        <STRONG>int</STRONG> <STRONG>werase(WINDOW</STRONG> <STRONG>*win);</STRONG>
14        <STRONG>int</STRONG> <STRONG>clear(void);</STRONG>
15        <STRONG>int</STRONG> <STRONG>wclear(WINDOW</STRONG> <STRONG>*win);</STRONG>
16        <STRONG>int</STRONG> <STRONG>clrtobot(void);</STRONG>
17        <STRONG>int</STRONG> <STRONG>wclrtobot(WINDOW</STRONG> <STRONG>*win);</STRONG>
18        <STRONG>int</STRONG> <STRONG>clrtoeol(void);</STRONG>
19        <STRONG>int</STRONG> <STRONG>wclrtoeol(WINDOW</STRONG> <STRONG>*win);</STRONG>
20
21
22 </PRE>
23 <H2>DESCRIPTION</H2><PRE>
24        The <STRONG>erase</STRONG> and <STRONG>werase</STRONG> routines copy blanks to  every  posi-
25        tion in the window, clearing the screen.
26
27        The  <STRONG>clear</STRONG>  and <STRONG>wclear</STRONG> routines are like <STRONG>erase</STRONG> and <STRONG>werase</STRONG>,
28        but they also call <STRONG>clearok</STRONG>, so that the screen is  cleared
29        completely  on  the  next call to <STRONG>wrefresh</STRONG> for that window
30        and repainted from scratch.
31
32        The <STRONG>clrtobot</STRONG> and <STRONG>wclrtobot</STRONG> routines erase from the  cursor
33        to the end of screen.  That is, they erase all lines below
34        the cursor in the window.  Also, the current line  to  the
35        right of the cursor, inclusive, is erased.
36
37        The <STRONG>clrtoeol</STRONG> and <STRONG>wclrtoeol</STRONG> routines erase the current line
38        to the right of the cursor, inclusive, to the end  of  the
39        current line.
40
41        Blanks created by erasure have the current background ren-
42        dition (as set by <STRONG>wbkgdset</STRONG>) merged into them.
43
44
45 </PRE>
46 <H2>RETURN VALUE</H2><PRE>
47        All routines return the integer  <STRONG>OK</STRONG>.   The  SVr4.0  manual
48        says  "or  a  non-negative integer if <STRONG>immedok</STRONG> is set", but
49        this appears to be an error.
50
51
52 </PRE>
53 <H2>NOTES</H2><PRE>
54        Note that <STRONG>erase</STRONG>, <STRONG>werase</STRONG>, <STRONG>clear</STRONG>, <STRONG>wclear</STRONG>, <STRONG>clrtobot</STRONG>, and <STRONG>clr-</STRONG>
55        <STRONG>toeol</STRONG> may be macros.
56
57
58 </PRE>
59 <H2>PORTABILITY</H2><PRE>
60        These  functions are described in the XSI Curses standard,
61        Issue 4.  The standard specifies that they return  <STRONG>ERR</STRONG>  on
62        failure, but specifies no error conditions.
63
64        Some  historic  curses  implementations had, as an undocu-
65        mented feature,  the  ability  to  do  the  equivalent  of
66
67
68 </PRE>
69 <H2>SEE ALSO</H2><PRE>
70        <STRONG><A HREF="ncurses.3x.html">curses(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>
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