<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>stack</title>
<link rel="stylesheet" type="text/css" href="csound.css" />
<meta name="generator" content="DocBook XSL Stylesheets V1.76.1" />
<link rel="home" href="index.html" title="The Canonical Csound Reference Manual" />
<link rel="up" href="OpcodesTop.html" title="Orchestra Opcodes and Operators" />
<link rel="prev" href="sr.html" title="sr" />
<link rel="next" href="statevar.html" title="statevar" />
</head>
<body>
<div class="navheader">
<table width="100%" summary="Navigation header">
<tr>
<th colspan="3" align="center">stack</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="sr.html">Prev</a> </td>
<th width="60%" align="center">Orchestra Opcodes and Operators</th>
<td width="20%" align="right"> <a accesskey="n" href="statevar.html">Next</a></td>
</tr>
</table>
<hr />
</div>
<div class="refentry" title="stack">
<a id="stack"></a>
<div class="titlepage"></div>
<a id="IndexStack" class="indexterm"></a>
<div class="refnamediv">
<h2>
<span class="refentrytitle">stack</span>
</h2>
<p>stack —
Initializes the stack.
</p>
</div>
<div class="refsect1" title="Description">
<a id="idp45263416"></a>
<h2>Description</h2>
<p>
Initializes and sets the size of the global stack.
</p>
</div>
<div class="refsect1" title="Syntax">
<a id="idp45264080"></a>
<h2>Syntax</h2>
<pre class="synopsis"><span class="command"><strong>stack</strong></span> iStackSize</pre>
</div>
<div class="refsect1" title="Initialization">
<a id="idp45317536"></a>
<h2>Initialization</h2>
<p>
<span class="emphasis"><em>iStackSize</em></span> - size of the stack in bytes.
</p>
</div>
<div class="refsect1" title="Performance">
<a id="idp45318352"></a>
<h2>Performance</h2>
<p>
Csound implements a single global stack. Initializing the stack with the <span class="emphasis"><em>stack</em></span> opcode is not required - it is optional, and if not done, the first use of <a class="link" href="push.html" title="push"><em class="citetitle">push</em></a> or <a class="link" href="push_f.html" title="push_f"><em class="citetitle">push_f</em></a> will automatically create a stack of 32768 bytes. Otherwise, <span class="emphasis"><em>stack</em></span> is normally called from the orchestra header, and takes a stack size parameter in bytes (there is an upper limit of about 16 MB). Once set, the stack size is fixed and cannot be changed during performance.
</p>
<p>
The global stack works in LIFO order: after multiple <a class="link" href="push.html" title="push"><em class="citetitle">push</em></a> calls, <a class="link" href="pop.html" title="pop"><em class="citetitle">pop</em></a> should be used in reverse order.
</p>
<p>
Each <a class="link" href="push.html" title="push"><em class="citetitle">push</em></a> or <a class="link" href="pop.html" title="pop"><em class="citetitle">pop</em></a> operation can work on a "bundle" of multiple variables. When using <a class="link" href="pop.html" title="pop"><em class="citetitle">pop</em></a>, the number, type, and order of items must match those used by the corresponding <a class="link" href="push.html" title="push"><em class="citetitle">push</em></a>. That is, after a 'push Sfoo, ibar', you must call something like 'Sbar, ifoo pop', and not e.g. two separate 'pop' statements.
</p>
<p>
<a class="link" href="push.html" title="push"><em class="citetitle">push</em></a> and <a class="link" href="pop.html" title="pop"><em class="citetitle">pop</em></a> opcodes can take variables of any type (i-, k-, a- and strings). Variables of type 'a' and 'k' are passed at performance time only, while 'i' and 'S' are passed at init time only.
</p>
<p>
push/pop for a, k, i, and S types copy data by value. By contrast, <a class="link" href="push_f.html" title="push_f"><em class="citetitle">push_f</em></a> only pushes a "reference" to the f-signal, and then the corresponding <a class="link" href="pop_f.html" title="pop_f"><em class="citetitle">pop_f</em></a> will copy directly from the original variable to its output signal. For this reason, changing the source f-signal of <a class="link" href="push_f.html" title="push_f"><em class="citetitle">push_f</em></a> before <a class="link" href="pop_f.html" title="pop_f"><em class="citetitle">pop_f</em></a> is called is not recommended, and if the instrument instance owning the variable that was passed by push_f is deactivated before pop_f is called, undefined behavior may occur.
</p>
<p>
Any stack errors (trying to push when there is no more space, or pop from an empty stack, inconsistent number or type of arguments, etc.) are fatal and terminate performance.
</p>
</div>
<div class="refsect1" title="Examples">
<a id="idp45328552"></a>
<h2>Examples</h2>
<p>
Here is an example of the stack opcode. It uses the file <a class="ulink" href="examples/stack.csd" target="_top"><em class="citetitle">stack.csd</em></a>.
</p>
<div class="example">
<a id="idp45329520"></a>
<p class="title">
<strong>Example 795. Example of the stack opcode.</strong>
</p>
<div class="example-contents">
<p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
<pre class="programlisting">
<span class="csdtag"><CsoundSynthesizer></span>
<span class="csdtag"><CsOptions></span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o stack.wav -W ;;; for file output any platform</span>
<span class="csdtag"></CsOptions></span>
<span class="csdtag"><CsInstruments></span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">0dbfs</span> <span class="op">=</span> 1
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="opc">stack</span> 100000
<span class="oblock">instr</span> 1
a1 <span class="opc">oscils</span> 0.7, 220, 0
k1 <span class="opc">line</span> 0, p3, 1
<span class="opc">push</span> "blah", 123.45, a1, k1
<span class="opc">push</span> <span class="opc">rnd</span>(k1)
k_rnd <span class="opc">pop</span>
S01, i01, a01, k01 <span class="opc">pop</span>
<span class="opc">printf_i</span> "S01 <span class="op">=</span> '<span class="op">%</span>s', i01 <span class="op">=</span> <span class="op">%</span>g\n", 1, S01, i01
ktrig <span class="opc">metro</span> 5.0
<span class="opc">printf</span> "k01 <span class="op">=</span> <span class="op">%</span>.3f, k_rnd <span class="op">=</span> <span class="op">%</span>.3f\n", ktrig, k01, k_rnd
<span class="opc">outs</span> a01, a01
<span class="oblock">endin</span>
<span class="csdtag"></CsInstruments></span>
<span class="csdtag"><CsScore></span>
<span class="stamnt">i</span> 1 0 5
<span class="stamnt">e</span>
<span class="csdtag"></CsScore></span>
<span class="csdtag"></CsoundSynthesizer></span>
</pre>
</div>
</div>
<p><br class="example-break" />
</p>
</div>
<div class="refsect1" title="See also">
<a id="idp45331792"></a>
<h2>See also</h2>
<p>
<a class="link" href="pop.html" title="pop"><em class="citetitle">pop</em></a>,
<a class="link" href="push.html" title="push"><em class="citetitle">push</em></a>,
<a class="link" href="pop_f.html" title="pop_f"><em class="citetitle">pop_f</em></a> and
<a class="link" href="push_f.html" title="push_f"><em class="citetitle">push_f</em></a>.
</p>
<p>Using this opcode is somewhat hackish, as you can read here: <a class="ulink" href="http://csound.1045644.n5.nabble.com/passing-a-string-to-a-UDO-td1099284.html" target="_top">http://csound.1045644.n5.nabble.com/passing-a-string-to-a-UDO-td1099284.html</a></p>
</div>
<div class="refsect1" title="Credits">
<a id="idp45334776"></a>
<h2>Credits</h2>
<p>By: Istvan Varga.</p>
<p>2006</p>
</div>
</div>
<div class="navfooter">
<hr />
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left"><a accesskey="p" href="sr.html">Prev</a> </td>
<td width="20%" align="center">
<a accesskey="u" href="OpcodesTop.html">Up</a>
</td>
<td width="40%" align="right"> <a accesskey="n" href="statevar.html">Next</a></td>
</tr>
<tr>
<td width="40%" align="left" valign="top">sr </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> statevar</td>
</tr>
</table>
</div>
</body>
</html>
distrib
>
Mageia
>
5
>
x86_64
>
media
>
core-release
>
by-pkgid
>
b707d9a4ee443103660a75ccb6e51334
>
files
>
2640
