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<H1 class="no-header">curs_scroll 3x 2025-04-05 ncurses 6.6 Library calls</H1>
<PRE>
<STRONG><A HREF="curs_scroll.3x.html">curs_scroll(3x)</A></STRONG> Library calls <STRONG><A HREF="curs_scroll.3x.html">curs_scroll(3x)</A></STRONG>
</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
<STRONG>scroll</STRONG>, <STRONG>scrl</STRONG>, <STRONG>wscrl</STRONG> - scroll a <EM>curses</EM> window
</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
<STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
<STRONG>int</STRONG> <STRONG>scroll(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>scrl(int</STRONG> <EM>n</EM><STRONG>);</STRONG>
<STRONG>int</STRONG> <STRONG>wscrl(WINDOW</STRONG> <STRONG>*</STRONG> <EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>n</EM><STRONG>);</STRONG>
</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
<STRONG>scroll</STRONG> scrolls the given window up one line. That is, every visible
line we might number <EM>i</EM> becomes line <EM>i</EM>-1. <STRONG>wscrl</STRONG> and <STRONG>scrl</STRONG> scroll the
specified window or <STRONG>stdscr</STRONG>, respectively, up or down per the sign of <EM>n</EM>.
<STRONG>o</STRONG> For positive <EM>n</EM>, line <EM>i</EM>+<EM>n</EM> becomes <EM>i</EM> (scrolling up);
<STRONG>o</STRONG> for negative <EM>n</EM>, line <EM>i</EM>-<EM>n</EM> becomes <EM>i</EM> (scrolling down).
A line that scrolls beyond the window boundaries disappears; <EM>curses</EM>
populates a new one emerging at the opposite boundary with the
background character; see <STRONG><A HREF="curs_bkgd.3x.html">bkgd(3x)</A></STRONG> (wide-character API users:
<STRONG><A HREF="curs_bkgrnd.3x.html">bkgrnd(3x)</A></STRONG>). As an optimization, if the scrolling region of the window
is the entire screen, the physical screen may be scrolled at the same
time; see <STRONG><A HREF="curs_variables.3x.html">curscr(3x)</A></STRONG>.
The cursor does not move. These functions perform no operation unless
scrolling is enabled for the window via <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG>.
</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
These functions return <STRONG>ERR</STRONG> upon failure and <STRONG>OK</STRONG> upon success.
In <EM>ncurses</EM>, they return <STRONG>ERR</STRONG> if
<STRONG>o</STRONG> the <EM>curses</EM> screen has not been initialized,
<STRONG>o</STRONG> (for functions taking a <EM>WINDOW</EM> pointer argument) <EM>win</EM> is a null
pointer, or
<STRONG>o</STRONG> scrolling is not enabled in the window (as by <STRONG><A HREF="scrollok.3x.html">scrollok(3x)</A></STRONG>).
</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
<STRONG>scroll</STRONG> and <STRONG>scrl</STRONG> may be implemented as macros.
Unusually, there is no <STRONG>wscroll</STRONG> function; <STRONG>scroll</STRONG> behaves as one would
expect <STRONG>wscroll</STRONG> to, accepting a <EM>WINDOW</EM> pointer argument.
</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.
SVr4 describes a successful return value only as "an integer value
other than <EM>ERR</EM>".
SVr4 indicates that the optimization of physically scrolling
immediately if the scroll region is the entire screen "is" performed,
not "may be" performed. <EM>ncurses</EM> deliberately does not guarantee that
this occurs, to leave open the possibility of better optimization of
multiple scroll actions on the next update.
Neither SVr4 <EM>curses</EM> nor X/Open Curses specify whether these functions
zero the attributes or color pair identifier of the background
character. In <EM>ncurses</EM>, they do not.
</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
4BSD (1980) introduced <EM>scroll</EM>, defining it as a function.
SVr3.1 (1987) added <EM>scrl</EM> and <EM>wscrl</EM>, redefining <EM>scroll</EM> as a macro
wrapping the latter.
</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_outopts.3x.html">curs_outopts(3x)</A></STRONG>
ncurses 6.6 2025-04-05 <STRONG><A HREF="curs_scroll.3x.html">curs_scroll(3x)</A></STRONG>
</PRE>
<div class="nav">
<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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