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    <pre><code>char **argv[] </code></pre> <p>Is wrong. It should be either <code>char **argv</code> or <code>char *argv[]</code>, not a mixture of both. And then it becomes a pointer-to-pointer to characters, or rather a pointer to c-strings, i.e., an array of c-strings. :) <a href="http://cdecl.org" rel="nofollow">cdecl.org</a> is also quite helpful at thing like this.<br> Then, for the access, sure. Just, well, access it. :) <code>argv[0]</code> would be the first string, <code>argv[3]</code> would be the 4th string. But I totally wouldn't recommend replacing stuff in an array that isn't yours or that you know the internals of.<br> On array resize, since you're writing C++, use <a href="http://www.cplusplus.com/reference/stl/vector/" rel="nofollow"><code>std::vector</code></a>, which does all the complicated allocation stuff for you and is really safe. Generally, it depends on the array type. Dynamically allocated arrays (<code>int* int_arr = new int[20]</code>) can, static arrays (<code>int int_arr[20]</code>) can't.<br> To copy everything in <code>argv</code> into a single <code>std::string</code>, loop through the array and append every c-string to your <code>std::string</code>. I wouldn't recommend that though, rather have a <code>std::vector&lt;std::string&gt;</code>, i.e., an array of <code>std::strings</code>, each holding one of the arguments.</p> <pre><code>std::vector&lt;std::string&gt; args; for(int i=0; i &lt; argc; ++i){ args.push_back(argv[i]); } </code></pre> <p>On your last point, since the standard demands <code>argv</code> to be terminated by a <code>NULL</code> pointer, it's quite easy.</p> <pre><code>int myargc = 0; char** argv_copy = argv; while(++argv_copy) ++myargc; </code></pre> <p>The <code>while(++argv_copy)</code> will first increment the pointer of the array, letting it point to the next element (e.g., after the first iteration it will point at c-string #2 (<code>argv[1]</code>)). After that, if the pointer evaluates to false (if it is <code>NULL</code>), then the loop brakes and you have your <code>myargc</code>. :)</p>
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    1. COThanks for your detailed answer. Too bad I'm not allowed to accept more than one answer.
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