Constants.html 4.5 KB

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  61. Next: <a href="Symbolic-Constants.html#Symbolic-Constants" accesskey="n" rel="next">Symbolic Constants</a>, Up: <a href="Expressions.html#Expressions" accesskey="u" rel="up">Expressions</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p>
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  64. <a name="Constants-1"></a>
  65. <h4 class="subsection">3.10.1 Constants</h4>
  66. <a name="index-integer-notation"></a>
  67. <a name="index-constants-in-linker-scripts"></a>
  68. <p>All constants are integers.
  69. </p>
  70. <p>As in C, the linker considers an integer beginning with &lsquo;<samp>0</samp>&rsquo; to be
  71. octal, and an integer beginning with &lsquo;<samp>0x</samp>&rsquo; or &lsquo;<samp>0X</samp>&rsquo; to be
  72. hexadecimal. Alternatively the linker accepts suffixes of &lsquo;<samp>h</samp>&rsquo; or
  73. &lsquo;<samp>H</samp>&rsquo; for hexadecimal, &lsquo;<samp>o</samp>&rsquo; or &lsquo;<samp>O</samp>&rsquo; for octal, &lsquo;<samp>b</samp>&rsquo; or
  74. &lsquo;<samp>B</samp>&rsquo; for binary and &lsquo;<samp>d</samp>&rsquo; or &lsquo;<samp>D</samp>&rsquo; for decimal. Any integer
  75. value without a prefix or a suffix is considered to be decimal.
  76. </p>
  77. <a name="index-scaled-integers"></a>
  78. <a name="index-K-and-M-integer-suffixes"></a>
  79. <a name="index-M-and-K-integer-suffixes"></a>
  80. <a name="index-suffixes-for-integers"></a>
  81. <a name="index-integer-suffixes"></a>
  82. <p>In addition, you can use the suffixes <code>K</code> and <code>M</code> to scale a
  83. constant by
  84. <code>1024</code> or <code>1024*1024</code>
  85. respectively. For example, the following
  86. all refer to the same quantity:
  87. </p>
  88. <div class="smallexample">
  89. <pre class="smallexample">_fourk_1 = 4K;
  90. _fourk_2 = 4096;
  91. _fourk_3 = 0x1000;
  92. _fourk_4 = 10000o;
  93. </pre></div>
  94. <p>Note - the <code>K</code> and <code>M</code> suffixes cannot be used in
  95. conjunction with the base suffixes mentioned above.
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