c-shell3.html

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<div class="CellBody"><a name="84841"> </a><b class="keyword">char</b></div>

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<div class="CellBodyC" align="center"><a name="84843"> </a>1</div>

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<pre class="CodeLeft"><b><a name="84845">x = 'A' 
x = (char)65 
x = (char)0x41</a></b></pre>

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<pre class="CodeLeft"><b><a name="84849">(char) x</a></b></pre>

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<div class="CellBody"><a name="84867"> </a><b class="keyword">double</b></div>

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<div class="CellBodyC" align="center"><a name="84869"> </a>8</div>

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<pre class="CodeLeft"><b><a name="84871">x = 11.2 
x = (double)11.2</a></b></pre>

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<pre class="CodeLeft"><b><a name="84874">(double) x</a></b></pre>

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<div class="CellBody"><a name="84900"> </a><b class="keyword">float</b></div>

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<div class="CellBodyC" align="center"><a name="84902"> </a>4</div>

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<pre class="CodeLeft"><b><a name="84904">x = (float)5.42</a></b></pre>

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<pre class="CodeLeft"><b><a name="84906">(float) x</a></b></pre>

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<dd><p class="Body"><a name="84908"> </a>Strings, or character arrays, are not treated as separate types in the shell C interpreter. To declare a string, set a variable to a string value.<sup><a href="#foot"><b class="FootnoteMarker">1</b></a></sup>
 For example:</p>
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<dd><pre class="Code2"><b><a name="84915"></b><tt class="output">-&gt;</tt><b> ss = "shoe bee doo"</a></b></pre>
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<dd><p class="Body"><a name="84916"> </a>The variable <b class="symbol_lc">ss</b> is a pointer to the string <i class="i">shoe bee doo</i>. To display <b class="symbol_lc">ss</b>, enter:</p>
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<dd><pre class="Code2"><b><a name="84917"></b><tt class="output">-&gt;</tt><b> d ss</a></b></pre>
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<dd><p class="Body"><a name="84926"> </a>The <b class="routine"><i class="routine">d</i></b><b>(</b>&nbsp;<b>)</b> command displays memory where <b class="symbol_lc">ss</b> is pointing.<sup><a href="#foot"><b class="FootnoteMarker">2</b></a></sup>
 You can also use <b class="routine"><i class="routine">printf</i></b><b>(&nbsp;)</b> to display strings.</p>
<dd><p class="Body"><a name="84931"> </a>The shell places no type restrictions on the application of operators. For example, the shell expression:</p>
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<dd><pre class="Code2"><b><a name="84932"> *(70000 + 3 * 16)</a></b></pre>
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<dd><p class="Body"><a name="84934"> </a>evaluates to the 4-byte integer value at memory location 70048.</p>
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<h4 class="H3"><i><a name="84935">6.3.2  &nbsp;&nbsp;Lines and Statements</a></i></h4>
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<dd><p class="Body"><a name="84937"> </a>The shell parses and evaluates its input one line at a time. A line may consist of a single shell statement or several shell statements separated by semicolons. A semicolon is not required on a line containing only a single statement. A statement cannot continue on multiple lines. </p>
<dd><p class="Body"><a name="98477"> </a>Shell statements are either C expressions or assignment statements. Either kind of shell statement may call WindSh commands or target routines.</p>
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<h4 class="H3"><i><a name="84939">6.3.3  &nbsp;&nbsp;Expressions</a></i></h4>
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<dd><p class="Body"><a name="84941"> </a>Shell expressions consist of literals, symbolic data references, function calls, and the usual C operators.</p>
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<h4 class="H4"><i><a name="84942">Literals</a></i></h4>
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<dd><p class="Body"><a name="84947"> </a>The shell interprets the literals in <a href="c-shell3.html#84951">Table&nbsp;6-11</a> in the same way as the C compiler, with one addition: the shell also allows hex numbers to be preceded by <b>$</b> instead of <b>0x</b>.<p class="table">
<h4 class="EntityTitle"><a name="84951"><font face="Helvetica, sans-serif" size="-1" class="sans">Table 6-11:&nbsp;&nbsp;Literals in the Shell C Interpreter</font></a></h4>

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<div class="CellHeading"><b><a name="84955"> </a><font face="Helvetica, sans-serif" size="-1" class="sans">Literal</font></b></div>

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<div class="CellHeading"><b><a name="84957"> </a><font face="Helvetica, sans-serif" size="-1" class="sans">Example</font></b></div>

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<div class="CellBody"><a name="84963"> </a>decimal numbers</div>

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<div class="CellBody"><a name="84965"> </a><b>143967</b> </div>

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<div class="CellBody"><a name="84967"> </a>octal numbers</div>

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<div class="CellBody"><a name="84969"> </a><b>017734</b> </div>

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<div class="CellBody"><a name="84971"> </a>hex numbers</div>

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<div class="CellBody"><a name="84973"> </a><b>0xf3ba</b> or <b>$f3ba</b> </div>

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<div class="CellBody"><a name="84975"> </a>floating point numbers</div>

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<div class="CellBody"><a name="84977"> </a><b>666.666</b> </div>

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<div class="CellBody"><a name="84979"> </a>character constants</div>

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<div class="CellBody"><a name="84981"> </a><b>'x'</b> and <b>'$'</b> </div>

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<div class="CellBody"><a name="84983"> </a>string constants</div>

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<div class="CellBody"><a name="84985"> </a><b>"hello world!!!"</b> </div>

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