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| <h3 class="section">5.9 strfry</h3> |
| |
| <p>The function below addresses the perennial programming quandary: “How do |
| I take good data in string form and painlessly turn it into garbage?” |
| This is actually a fairly simple task for C programmers who do not use |
| the GNU C library string functions, but for programs based on the GNU C |
| library, the <code>strfry</code> function is the preferred method for |
| destroying string data. |
| |
| <p>The prototype for this function is in <samp><span class="file">string.h</span></samp>. |
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| <!-- string.h --> |
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| — Function: char * <b>strfry</b> (<var>char *string</var>)<var><a name="index-strfry-579"></a></var><br> |
| <blockquote> |
| <p><code>strfry</code> creates a pseudorandom anagram of a string, replacing the |
| input with the anagram in place. For each position in the string, |
| <code>strfry</code> swaps it with a position in the string selected at random |
| (from a uniform distribution). The two positions may be the same. |
| |
| <p>The return value of <code>strfry</code> is always <var>string</var>. |
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| <p><strong>Portability Note:</strong> This function is unique to the GNU C library. |
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