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copied!<ol> <li><p><code>dPtr</code> is being used to move through the string and modify it. <code>dest</code> is being kept as the beginning of that modified string, eventually the return value of the function. At the end of each loop iteration, <code>dPtr</code> will point to the end of the modified string, and used for each successive <code>strncpy</code>. Ultimately the function returns a modified string, and <code>dest</code> is needed to keep track of it's beginning.</p></li> <li><p><code>subword</code> is being null terminated presumably so that only characters in <code>subword</code> will be copied into the result in the <code>strncpy</code> within the loop, but this actually isn't necessary with the use of <code>strncpy</code>. The function moves backwards through the string looking for dashes. For each hit, <code>subword</code> is the next dash-delimited substring. The substring is a piece of memory <em>inside</em> the original string, which isn't null-terminated. If you were using <code>strcpy</code> then you'd need null-termination of <code>subword</code>, but since you're using <code>strncpy</code> the null-terminators shouldn't be necessary: just be careful with your <code>n</code> values as the <code>strncpy</code> limit. This code null-terminates <code>subword</code> <em>in place</em>, i.e. by sticking null characters inside the original string argument. Which leads to #3:</p></li> <li><p>As for undesired behavior, the function does it's work by modifying the original string argument - it's putting those null terminators for <code>subword</code> into the source string - even though it's keeping it's own buffer for the modified and returned string.</p></li> </ol> <p>Finally, the code could do without <code>dPtr</code> by using <code>strncat</code> operations rather than <code>strncpy</code>.</p>

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